What are the disadvantages of HP and Dell SANs

Hi,

I need to deploy SAN of 3-4TB with MS dynamics AX and some other databases. I can see Dell offers CX4-120 and CX4-240 as options while I could see HP 6400 and 8400 (or 4400?) as good options.

Can anybody tell what are the drawbacks of these SANs? I have seen a lot of advantages and differences between these models but I am not sure how durable they are, or what about wear and tear or service issues from vendors etc.

Nikhil