Disclaimer: This first paragraph is my "Cowboy" side, refer to the second one for my "Professional" side.
To be honest I would say it's pretty unlikely to impact you from an IOPs standpoint enough to notice, especially if those VMs will be used for standard office computing considering how high IOPs are on most SSDs. In other words, if you have the throughput and storage space to handle the demand, if your SSDs have 50k IOPs each (IOPs do vary wildly by model in some cases though) then even in RAID 5 you should be fine.
Without more details it's not really possible to say anything with certainty though. I'd suggest crunching the numbers. Your answer will obviously be directly affected by the number of SSDs per array, IOPs per SSD, number of arrays, IOPs requirement of the VMs, and of course any overhead for your RAID. Essentially, find out what kind of IOPs, throughput, and storage space you expect to use, give yourself some overhead, and build your arrays with those numbers in mind.
~LikeABrandit