I use a upright freezer as a ferment fridge, it has shelves with intergrated cooling in them. I've readjusted the shelves by bending them to fit 2 fermenters it. I've also used it for kegs to where I have bent shelves all th way back to the wall and cable tied it i place. Then rebent them back into place again for fermenter, mind you I would expect it to last long if I was going to do it all the time. out side of that I've found they work great. the main point I'd be looking at is the flexablity of the shelves and whether your fermenters will fit even if you have to bend the first and 3rd shelves back to the wall.