I am running Cacko 1.21b/c860 and just finished testing 3 different MAME implementations with the same pacman clone.
MaxMAME: Very slow almost unusable.
Both MaxMAME and xmame.SDL did a great job of running as close to full screen as possible, however slow. Both use SDL. I used SDL libSDL_1.2.6-zports-4_arm.ipk. I am not sure if xmane.SDL used the zports version or not it may have been static and I do not have ldd installed.
zmamefull: Fast, almost perfect with good sound. If I enable overclock it is right one with sound, however not full screen and does not use SDL. With zmamefull a pixel is a pixel and attemps to scale cause it to crash with no error. Y scale seems to work. X does not.
What are others seeing?
What are you all using?
Is there a combination of SDL and MaxMAME/xmame.SDL that works well?
What are your settings?
IMHO QWS is the bottleneck. Are others with Advmame on pdaXrom getting good performance?