Choosing a SAN solution

We have been looking into two SAN solutions to expand our VMware infrastructure.  We currently have 1 VMware host with local storage and it is not enough storage or resources for our needs.  In addition the host is running on an older machine at this point and needs to be replaced.  We also want to have the benefit of redundancy - hence the reason for the SAN.

Part of this solution entails a second, lower level SAN for our DR site.  We've been looking at the EQ 6100 (production) and EQ 4200 (DR) and the VNX5300.  Both are coming back to us with their prices but it looks as though the VNX solution will be about $30,000 more than the EQ solution.

My first question is regarding the TCO.  Dell says their model is better because there is no "rip and replace".  EMC says their model is better because if you need to add a bit more down the road you don't need to buy a whole new SAN.  I'm sort of leaning towards the Dell approach.

My second question is, from what I've read online the consensus seems to be the VNX is a more powerful machine potentially and all things being equal, many people are opting for the VNX.  However in my situation is there any justification to spend that much more for the VNX?

I appreciate any input and suggestions.

Thanks.