Accurate sound emulation (Paula) is quite hardware intensive. Even on my old dedicated "amiga" pc box (Athlon64 3400+) I was left wanting more from time to time when using Winuae, although I much prefer Amithlon, which is faster on same hardware and more authentic feeling (much less reliant on a host system), so that could be part of my bias when it comes to using an amiga emulator. This may not be an option for you however if you have particular software needs (although nuldepah reroutes paula audio to ahi, so still may be an option for you.)