I just opened my revo and first put in my maxamps 3s 1550 lipos and they fit perfectly. The battery doors close securely and the 16 gauge wires fit nicely through the wiring notch, while the align connector tucks nicely into the beveled area of the battery compartment. Then, however, I tried the 1550 3s Rhinos I have stocked up on, which are only about 1mm thicker and it is a disaster. The packs will not allow the doors to close and the 12 guage wire is way too thick for fitting into the wiring slot. I managed to get one of the latches to snap closed. Then, I felt like I was going to break something trying to get it undone after the second latch wouldn't even come close to closing. Specifically I'm talking about the 1550 20C 3S Rhino packs from hobby city. This really is shocking as I've had both types of packs for over a week and they seem so close in size I thought that it wouldn't make a difference. I had already made some parallel deans to trx Y adapters for using the 6 rhinos I have invested in. It looks like I will now have to make permanent mods to my e-revos in order to use the rhinos. Looks like with the minis, its going to go beyond a matter of millimeters.