Fruit Trees in Tall (Barrel) Raised Beds?

I am currently building my first outdoor garden using repurposed 55 gallon barrels, and I just got the drums today.

I was wondering - would it be a bad idea to transplant a fruit tree in a barrel the second year (after things have settled) or direct sow a seed or pit in the first year?

I was thinking that I could plant plum/peach/etc trees and treat them like trees in any other container, but I wasn't sure if there would be additional issues due to the 3-foot (0.915m) height of the drums.

Any feedback or suggestions would be appreciated. I know that the trees won't grow as big or fruit as much, but I'm thinking that I might even be able to take a tree or two with me when I move by taking some of the barrels.
(if nothing else, I'll definitely want some of that excellent hugel dirt)

The largest thing I've grown in a barrel is a blueberry bush, and she is still young, less than 5 feet tall.
I have considered growing trees in barrels,  but I'm always concerned they will suffer once they become root bound.
The work that making a barrel into an air pruning container is not insignificant.
Of course a tree in a barrel would need to be heavily pruned anyway,and maybe root bind would just contribute to the dwarfing of the tree without hurting it otherwise?

No matter what, using lots of light weight amendments like perlite and including a way to drain the barrel will make any eventual move much more doable.