Thanks Toxie, I can confirm that the graphics glitches are gone in Batman Forever and it now seems to play at a better speed, but it might still be a bit slow which shows in one place in particular;
https://youtu.be/IOu6avRn3t4?t=699
This shows the "Rooftop Chase" video mode, vpinmame seems to still run noticeably slower compared to that video, it makes the mode very easy and is probably is probably close to half the speed of the original hardware?
*edit*
I just did an un-scientific test, using vpinmame.dll it takes about 8.5 second to get up the wall (where the 10 million barriers are), in the original machine (in the video) it takes about 3.5 seconds, so its over twice as fast (I'm running on a decent rig so it's not my hardware).
The display board CPU is definitely a 68000-12 as the diagram shows it as that, but there is a 24Mhz crystal on the display driver board.
*edit 2*
This is current mainline MAME's CPU speeds, seems the 6808 and 6809 are both clocked too slow;
M6808 ("decocpu:maincpu") cpu 4000000 Hz
M6809 ("decobsmt:soundcpu") cpu 1789790 Hz
TMS32015 ("decobsmt:bsmt:bsmt2000") cpu 24000000 Hz
M68000 ("decodmd:dmdcpu") cpu 12000000 Hz
Edited by Sixtoed, 30 March 2020 - 10:08 AM.