I am in the process of placing an order for a new Dell/EMC CX500 SAN and
would like to get your recommendations on which brand and model of fiber
switch other people are using?

These are the models DELL resells.

Brocade SilkWorm 4100
McDATA Sphereon 4700
Brocade SilkWorm 200E

I am looking for the pros/cons/experiences/recommendations.

Thanks