I've never used one myself, but I would assume they would work, as they can be used for frogs. However, they're probably thinner than the fish keepers, to allow heat to enter easier. I might use it for a bit, but not for an extended period of time, in case it wore down over time.
I was actually looking into using a storage container! The only thing that shied me away from it was the rigid tops, it's hard to find CLEAR clear one, and I would have to make a breathable lid.
I did go ahead and buy the Herp Haven. The lid does have a round pop out thing that I could pull the wire from the heater through.
PLUS, I found one with a grey lid so it's not some ghastly neon color.