It depends a lot for what you need the audio.
For myself (as non musician or audio editing person) the two main reasons for having sound card in classic Amiga are:
1. playing mp3 files without cpu-load with full quality
2. having a mixer for Paula, CD-ROM, TV-card and AHI-audio.
I have both PCI and Zorro bus in my Amiga and sound card is Delfina Lite. Soundblaster wouldn't do the 1. thing, so that's why I prefer Zorro cards. Delfina Lite was cheap when I got it... if the money wouldn't have been the issue, then I'd got Delfina Plus instead

Paula is bit faster for games etc, so I use it for those. Only music needs the better quality IMHO.
Sampling is also easy and good quality with sound cards, but never actually needed it
