Is that Yeah Racing pack a direct fit because the edges are rounded like a "normal" stick pack is? Same theroy would apply with the new Trinity Intellect pack? Those seem to go a bit further and use actual stick pack "end caps", which would suggest they are indeed a drop in pack. The spec'd size seems pretty close to a Nimh stick pack.

Has anyone tried out lithium packs in an M04? I got my 2 cell Max Amps pack into my M03 with just a little help from my dremel. I'm wanting to see what that 2 cell will do in the M04.