(BDP 11) Branch Line Tank Engine

Link for voting if you like my submission: https://www.bricklink.com/v3/designer-program/series-11/4855/Branch-Line-Tank-Engine I am also working on a a version powered with circuit cube motors for a self-contained shunter. (But I don’t think I can say that on the submission page). I haven’t used circuit cubes before, I was wondering if anyone could tell me how well the battery would hold its charge running two motors? Or would it be better to only use one? I ordered some but it’ll be a...