Desktop and Enterprise drives are really only labeled for SATA disks.
All SAS/SCSI drives are Enterprise, and as far as specific hosts you'd want to ask them exactly what drive model is used.
Honestly SATA = lower end performance, but gives you amazing storage capacities 1-2TB
SAS/SCSI = high performance but smaller capacities with a max of 450GB
In all honesty individual drives dont matter too much and what you really want is a RAID enabled system to protect them in case of a single drive failure. Additional off server backups are just as important.
Check out
www.RealityCheckNetwork.com or hit me up on ICQ directly 4930562 - I can spec out a server for your specific needs that's fully protected and priced for Desktop or Enterprise level performance/functionality.