Didn't notice you post ,Did you use shaders or overlay that can cause the drop ?and I can already see there is performance differences, the game Bust A Move stutters when played on Mame2010.
So you have to weigh more Roms against performance.
i have just tested pbobblen and it works at 100% (59,1fps) sound is just perfect and no stutters.
edit: but BTW your are right , mame 0.139 is c++ code and under 0.136 it was C , moving to C++ has caused a general slowdown + the fact that mamedev tend to be more accurate version by version ( less hack , less speed).
Last edited by rioray,