I just sold my MAS Player Pro version a few days ago
I had it on my 68030 CD32/SX32 pro using AMPlifier and it worked excellent. Takes like 10% CPU load though. But I ran SCALA presentations while MP3's were playing and it ran great.
I highly recommend AMPlifier over AmigaAMP....AmigaAMP is best used for gfx card users.
Also use the simple MUI skin if you have to.
although I used it with the main WinAMP skin and it worked good.
Get the CLI MAS commands from Aminet too!
EDIT: forgot to mention....I also used it with my plain 7mhz A600 2MB chip and it worked perfect except for the software which was not very responsive....but the music played perfect as long as you werent multitasking.