I think for anyone on a tight budget, these civilian version Scepters that Road mentions here are the best bang for the buck.
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:
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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:
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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.
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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.
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Hope this helps you.
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