Best server for 7.1 ?

Hi all. Does anyone have pet choices for 7.1 (or greater) servers? The servers should be : Reliable Fast Capable of handling 300+ users, 40 Gigabyte database, online transaction processing and queries. Have fault tolerant harware or at least reliable disk mirroring (ie mirroring which works if all of your disks go down simulataneously). Reasonably priced Upgradeable Great technical support. A vendor with a relatively stable future in the market place.. Any ideas anyone? Anybody swear by their machine?