Sun has got the couple of serices of servers, there have enterprise and sun fire server line are stable, expensive and reliable. Even thought they calles v880, v440, v.... etc as sun fire, but the internal arch. is different, bus speed is different, back plan is different and you dont have domain concept. These server are more sutible for workgroups. The ent. or fire series are

Sun Ent. 3500, 4500, 5500, 6500, 10K
Sun Fire 3800, 4800, 6800, F12K, 15K

These server are more reliable, logical domain, etc. if you want to see the performance, through put you can replace v880 with sunfire x800 series.

Good luck