I would recommend defining exactly what you are looking for, then identify the vendors that can provide it.

Here are some questions to ask your group.

1. What is the primary purpose of the Storage?
2. Will we ever want to network or SAN attach this storage?
3. What features of a RAID Array are most important, in order?
a. RAID Striping and Parity? (fault tolerance across disks)
b. Caching and speed of reading data?
c. Caching and speed of writing data?
d. 99.999% uptime?
e. large capacity storage?

These will start to provide you with a basis on what hardware vendors to look for, and what the group is looking to achieve.

This will help you determine who has the solution that will fit your need, and budget, without drawing out the process...

RE: The Apple Store (U.S.) - Xserve RAID