Do not buy DELL is the only advice I can give you.
We recently a R720 and MD3200 and installed. We installed ESXi 5.5 on the R720 and tried installed a few VMs onto it; after about a week; the link between the R720 and MD3200 is severed.
Dell folks asks us to send the ZIP logs to them; however their email addresses will without telling anyone drop any emails with the ZIP; so after sending the log there was radio silence 4 hours and then I called up again and asked why they hadn’t gotten back. Apparently they never received the email; they then give me an FTP login and password to upload the log files.
Afterwards 8 hours at the datacentre; they finally send somebody over to replace the SAS HBA Adaptor on the R720 which they “diagnose” as the cause of the problem. I told them to bring 2 SAS Cards as we have something mission-critical running and would prefer to have back up but the support person tells me that the whole of Hong Kong had only 1 card so after 8 hours at the datacentre. The guys turns up and the SAS card is a dud and the system would not even recognise it and he tried everything but finally realised that the replacement card was actually broken. They then send for 2 SAS cards to be delivered after 2 hours; but hold on a second; they mentioned that the whole of Hong Kong had only 1 SAS HBA adaptor but now after 3 hours at 8 p.m. on a Sunday evening; suddenly Hong Kong has replenished its stock with 2 more adaptors.
One week later, the same thing happens and they tell us that it is to do with our configuration and nothing to do with hardware; they tell us we are not using their best practice; we alter the entire configuration as per their instructions and a week later the same thing happens. I send the log files over to the support email but as usual it does not get through and I tell them to take away the whole machine to get it fixed.
Don’t use DELL, it’s run by monkeys.
On a separate note, we have another deployment which was almost exactly the same configuration using DELL running in a different datacentre that never had any issues but we’ve not had to deal with DELL support. So if you buy DELL, you better pray that the hardware you bought is 100% working; otherwise a nightmare awaits.