Before anything else, please note that HP will not be responsible for any Controller issues/data loss that could happen when using non-HP branded devices in their systems (the retail SSDs aren't even in their supported hardware listings). Does this mean using these SSDs is a bad idea? Not directly, but it's something you should always have in mind when deploying the machine.
I have successfully placed a 2,5" Intel 520 Series SSD in a HP NHP 3,5" bay (using some dualsided tape to secure it on the EXACT position where it slides into the SATA-connector and makes firm contact, so getting the position right and securing it is essential.
This was in a HP ProLiant ML110G7, which has a B110i controller (basicly the small/cheap line of ProLiant machines best suited for light workloads). I have only done short testing runs but running Win2008R2 felt VERY fluent, more so then running on the original 10K SAS drives that were in the machine before. But I'm gonna leave it at that seeing I didn't stress it to the max for extended periods of time OR didn't do benchmarks either so it's all just a subjective feel about it. So is it possible to fit it in? Certainly. My B110i controller did detect it nicely, the Array Configuration saw it as an SSD and adjusted as such.