...I thought someone would have answered this better than what I can
If you can get a bin/cue, grab it...
it's just so much easier to burn, and will save you a lot of grey hairs
The problem I have found with iso+mp3 is that
You never really know what you're getting
Unfortunately, most of the ones I've seen had the same problems as Snatcher (but not all)
I have an out-of-sync Lunar, and I refuse to play the game until I can buy and dump the real deal
The cue sheets are rarely included with iso+mp3s
You can write your own, but without knowing the particular index times, pregaps, etc., by using a .cue from an ISO+MP3 dump from an original disc, it doesn't really help
Not all CD audio-to-mp3 rippers are the same
...as evidenced by elportal's version of Snatcher
The times weren't correct to begin with. I wonder if that dump is actually an iso+mp3 copy of... an iso+mp3 copy of.... etc, since the track times were so off-kilter
Because audio segments are cued & called from the game on what time they appear on disc, if some tracks are off by several seconds, that might cause problems
...this is all just my opinion, I don't claim to be a know it all... I could be wrong on many points here
Generally, I don't like to deal with burning iso+mp3 unless I have no other choice. It's not that I feel the audio quality is bad, I've never been as satisfied with the burns as those from a .bin/.cue
If it plays well in perfect sync in Gens, then I do a burn
I think where most of the burning/sync problems come from, is that the audio tracks are not the correct lengths in seconds...so even if the cue is good, it won't matter, it'll still be out of sync
Not sure if the iso would be needed to be converted to Japanese using SCDCONV (or if it can), if you're sending it to someone with a Jap SCD... I must admit I have not tried that
Hope this helps somewhat. You could always burn and try it in Gens before you send it
Eidleon's Inn has a Japanese Sega CD BIOS, I think