Extreme Tools 41" Question

[DirtyPhish]

I am going to get an extreme tools roller chest, 41" roller only but may add the top chest later (not sure I need the storage). This will go in my garage, it will get moved from time to time but does not need to move around much. With that said, could someone give me their understanding of the difference between the EX and the PWS. The models would be the 4111RC. They appear to be very similar to me.
Thanks in advance!