Gurus

I want to buy an old Sun Workstation/server, SPARC 5 or SPARC 10. Here are my questions:

1) Which of these servers would gurus recommend?

2) Oracle recommends at least 256M of RAM for Oracle 8i install. Would 128M of RAM be ok for install practice and testing???

3) Any other additional tips??? I know nothing about Sun servers.

Thanks a lot in advance