@barbudreadmon OK, so I tried again with the list of games you mentioned last time. Played every game about 5 minutes and had Frameskip = 1 for all of them from the beginning. I also enabled Cyclone (except for R-Type Leo, I think). This time I enabled the FPS counter and jus took notice how it behaves, I think the final RA log message about dropped frames is not so relevant.
Both cores play almost the same, there's no notable difference between them as far as I played.
rtypeleo - noticeable sound glitches (not so annoying), default runs at about 48 Fps. Increasing Frameskip to 2 makes it go to 50-52, but it's noticeable it's not running at full speed. Almost passed the first boss after the asteroid field.
firebarr - slowest of all, default (gcc) runs at about 48fps, but the sound artifacts and slowdown are more noticeable than for rtypeleo. The clang core runs about the same (46-48), but not better. I didn't increase the frameskip to 2, seems the game is quite taxing.
killbldp seemed to run fine, at about 60 fps, there's no noticeable slowdown. I played a match in both cores, seems fluid (remember it's still with frameskip = 1). If I remove the Frameskip, the FPS is around 58-59, but no noticeable slowdown.
svg this one I tested more. I noticed that if I pick one of the first characters, the FPS is ok (around 59), but if I pick for instance Wells, which has the 2 spinning blades animation, it dips to 55 for the round. Running again with frameskip = 2 makes the FPS go up again to 58-59.
I re-tested sfiii2 with frameskip = 1 and looked at the FPS, seems to be around 58, still very playable to me (I have to learn to block though, I got kicked out from the first match). Game was still in widescreen mode.