Welcome to A.org!
My personal Amiga use consists of "hobbyist" use and the retro/nostalgia scene of old games and demos. I rarely use mine for any real productive work though.
If you're prepared to spend $$$$ on expanding the A2000 or A3000 with a graphics card, CPU/accelerator board, decent sized hard drive and network card, you'll end up with a usable machine but in terms of performance, it won't match a modern PC, or even an Amiga emulated on a modern PC...
Anyway... dig out those old Amigas and get them running some great old games and demos!
- Ali
