Question about Mixing E series and X series Intel cpu's in a 2012 r2 hyper-v cluster

Hello,

 I had a quick question on a cluster. Since this is a production cluster I wanted to double check for clarification.  Currently have a 3 node 2012 R2 hyper-v cluster. The servers are all Dell R610's with Dual Intel E5540 processors.  I wanting to introduce a 4th node into the cluster only I was thinking of doing an R610 with Dual X5570 processors for a little more power.  My questions is, since these are all R610's and the processors are all from the same generation/release date, would I still have to go through and mark the checkbox on all the VM's for the "migrate to a physical computer with a different processor version"?  Or since they are the sam Generation would everything work as normal.  Any other pitfalls I'm missing?

 Thanks.