Im currently using IOS version. I was wondering the difference between IOS and MAC version. Can the default number of bars in a row be adjusted in MAC version? Any difference about quality of sounds? etc
Yes you can change the number of bars per system in the Mac version as well.
In terms of features everything you find in the iOS version is present in the Mac version. Both versions are 100% compatible and can be synchronised with iCloud easily.
The Mac version even has some extra features such as customisable drum notation. It was historically there before the iOS version