[raphlinus]

Emulators add a lot of extra latency, both on input and on display. Actually it isn't so much the emulator as the host os, with its compositor etc. An FPGA has the possibility of running with dramatically better latency. Similar issues go for startup time.

[Jaruzel]

Currently though, FPGA emulation of the Amiga hardware isn't 100% perfect (but good enough for almost all tasks).

Also, last time I checked, it also doesn't have AGA support yet, so there's no proper Amiga 1200 or 4000 emulation just yet.

The FPGA Amiga stuff is all open-source, so hopefully the emulation will get there eventually.

[MagerValp]

Both the MiniMig and FPGA Arcade cores support AGA these days.

[bni]

Actually this has been solved recently in WinUAE by implementing "Beam Racing Lagless VSync"