Not only were they arcade perfect ports, many arcade games coming from Japan used the Sharp as a dev environment...so they pretty much were the arcade games.
Ah, I didn't know this, makes sense though as they were 'perfect' (as far as my memory goes).
Typically the arcade to Amiga conversions were ranging from so-so to downright awful (with some notable exceptions like Pang which as I recall was very faithful), so I was amazed at seeing him loading up these arcade perfect versions on his X68000.