I purchased 3 rugged 5gal diesel jugs (Scepter made) from my local West Marine supply house here on the Maine coast. I've had them for years, in and out of my trailer (with a coarse bed-liner surface) and van and in all sorts of weather and environments with no problems, undue bloating, or obvious wear.
Cheap, too, compared to Scepter Military Fuel Cans, which are near impossible to find in the states, though more available in Canada. I do know a guy in El Paso who has two used MFCs if you're int'd, though think he wants $80ea.
The Scepter jugs I have, meant for fishing and sailboat industries, are a lot thicker than typical fuel jugs for homeowners, though not quite as thick as their MFCs. Like I said though, plenty rugged for the abuse I give them on a regular basis.
Took these images just now, having just fueled up recently in case local stations close during the virus crisis:
Here's another source for these same jugs, where they are $26.90 ea. I think I paid $50 for two yellow diesel Scepters at West Marine three years ago.
Scroll down on that page and you'll see the Wavian jugs, too (of rolled steel), which are popular with a lot of adventurers. I have no personal experience with them, preferring the non-rusting and probably longer lasting benefits of thick plastic. I have no experience with the site, zoro.com, that they're on, either.
If looking for great US Govt MWC, for water, you can get them in America from https://www.buylci.com/water-can-5-gallon.html. I have three from them and one from the military and find absolutely no difference. LCI contracts with the US Govt, from what I understand, and produce genuine military issue. Wish they made MFCs as well.
I've had these water jugs for years, too, and have found after extensive testing that fitting them with o-rings, as you'll find a lot of adventure threads suggesting, has no benefit in real practice. They get a lot of real practice with me, too, as much time as I spend in the desert.
Here's an image of the MWCs from last year when doing an article on sanitizing procedures:
The black 5gal jug is from Front Runner Outfitters and is my daily refill jug for the trailer tank, as it has a built-in and recessed tap on a bottom corner.
As for Roto-pax fuel containers, I have a couple for diesel, and have found them to look cool and all, but not be as practical for my use. I leave them in storage unless going on adventures where I think I may need them in addition to the 41 gals of fuel I can already carry.
They're fairly rugged, and thin dimensionally, making them easy to pack in narrow places. Though if carrying on the outside of your vehicle or trailer and exposed to the sun and weather, they tend to bloat and need venting more, like daily or couple times/day.
Many have complained of seepage leaks along seams. I suspect that's more from user error, overfilling (not allowing for expansion of cold fuel) and overexposure to the elements. In any event, since I carry my jugs out of sight, sometimes in the van, any potential seepage problems makes them less desirable for regular use.
Rotopax are expensive, too. I may sell mine in favor of getting more Scepter marine use jugs.
I have an issue with Rotopax leaking. The carb-compliant nozzle that comes with them needs to be replaced. Rotopax has replacement nozzles available on their site. Still you have to make sure the cap is on good and tight. On the plus side. They are easier to store and easier to handle than the 5 gallon containers.
This setup keeps the majority of the bed open and the containers secure. Same amount of fuel as the 2 Scepter MFCs
The 1 gallon I carried on my bike never had an issue. I still replaced the nozzle and I still placed the container on the bike so the cap was on the other side away from the exhaust.
For what it's worth. I wrecked that bike last July. The bike was totaled. The locking T-handle had marks where it hit pavement and slid and I couldn't open it. The Rotopax container also has signs of impact and slide marks. It stayed securely mounted and didn't leak. Even if I didn't
The Scepter MFCs will, with no doubt, also be able to take such abuse and the marine Scepter fuel containers probably have the same wall thickness as the Rotopax. I'd avoid the regular homeowner containers. You don't want gas or diesel all over your gear after going over a rough patch or, worse, if you wreck.
If you are worried about gasket replacements, etc., for the Scepter MFC. DS Tactical can sell you those. They just can't sell you the container itself. Bought the gasket, the MFC wrench, and fuel spouts from them.
I have a rear bumper on order and it will have a jerry can holder. I may swap the 3 fuel rotopax with water and go back to the MFCs if they fit.
I use the older NATO style steel jerry cans. I mention this because due to their weight and the lack of a fantastic pour-spout option, I've switched simply always using a rattle-ball/ez siphon for refuelling.
It does make it harder to get that last couple of ounces out of the can, but OTOH I always ended up pouring/leaking that much onto my hands and the ground anyway whenever I tried to use the various clamp-on spouts. In the early days, I just used a ratchet strap to hang the can from the side-rail of my roof rack. I now have little "feet" on my quarter-window utility rack where I mount my traction boards, etc. I now just prop the can up on the foot (and use one hand to just hold the can against the rack) so the other can is free to work the siphon.
Sorry, I didn't mean the ratchet cap and ring, but the locking slip-ring around the spout itself on so many fuel jugs in the US the last several years.
@buckwilk : Here's the images of the finicky spout on the Scepter Marine jerry cans I promised:
You have to twist and push it down to unlock it. Doesn't always work as easily as one might like. There's a spring in there.
Unlocking the slip-ring lets the spout push down into the cap when you're pouring and allows the fuel to flow.
The spout has a small air vent built in, which slows the filling process compared to the older free-flow spouts on jugs with vents at top rear:
There is a ledge point (red arrow) that is meant to push against the top edge of your vehicle's filler tube so the spout stays pushed in. Doesn't always work that way. I usually hold the spout in with one hand, supporting the front of the jug, while lifting the rear with my other hand to pour.
Some filler tubes on newer vehicles have a double door arrangement, too, making this type of spout harder to use.
As posted previously, I have a single racing jug-type spout on the way to make pouring easier. No sense fitting all my jugs with them; I'm just getting one for my diesel jugs and will switch it as needed. Then if I like it, will get another for the gasoline jug.
I need to get another gas jug too, matter of fact, for my kid to keep home for the lawnmower. I'll take mine with me adventuring for my Honda gen until I convert it to propane.
NOTE: As mentioned in the coronavirus general conversation thread, some businesses are giving letters to their workers, evidently, in case travel and fueling up becomes restricted in places.
I know I'm keeping extra jugs around and full.
"I love the smell of diesel in the morning..."
(Yep, we had a good snow last night on the coast of Maine. Looks wicked nice out this morning with the sun out and warming up.)
I simply replaced the carb spouts on the rotopax with these. I do more harm to the environment by using those and spilling gas than I do by using the simple spouts.
The fuel spouts for the MFCs I mentioned above a really great. They're self venting and you can completely invert the canister with very little leakage. Just a few drops of fuel until the airflow begins.
It makes for a simple one-way valve. Held vertically, the ball seals the end of the tube. You activate the siphon by cycling the tube up and down inside the reservoir (jerry can, etc.). Moving the tube rapidly down forces fuel into the tube past the ball, which then re-seals the tube on the upstroke. It basically lets you prime the siphon tube by just cycling the tube up/down a handful of times. Once liquid is flowing through the tube (siphon established), the valve stays open wide enough to permit flow.