I hear a lot of neg about the Blade 1500, however I have found mine a pretty good Single CPU UltraSPARC system.
Very quiet (remember to tune the power management config file!), as fast in practical terms as my V210 (2x1.34GHZ), dual drive, (80+120 in mine and the upper IDE limit is not really an issue for me on this system), and looks neat even today (the cool factor).
Have not had any reliability issues, and this is an 2004 production machine, so going strong for 7 years (5 of them in Glasgow University VLSI lab where it must have been plenty used).
If you really want a quiet, low power at <300W (MUCH lower than a 1000/2000 - which apparently run at 650W!) machine its not a bad choice.
I run headless so I can't comment on the XVR video cards though (mine has an XVR 100).
Sun Blade 2500 'Silver' Workstation - Dual 1.6 USIIIi, 4GB, 146GB SCSI, Solaris 10U9
Sun V210, 2x1.33 USIIIi, 8GB, 73GB 15K, Solaris 10U9
Sun V100, USIIi 550, 1.5GB, 40GB, Debian Lenny 5.X