SATA SSD limited by interposer board?

HI folks,

We have a couple of PE1950's with 3.5 inch SATAu disk carriers and SATA disks, and are considering replacing a couple of the disks with SSD's - for the usual speed reasons.  I suppose that we could use SAS SSD's, but SATA SSD's are easier to obtain and have more available models.  SATA SSD's would of course use the existing "interposer board", so the question is, does the interposer introduce any constraints (such as speed limits) which make SAS drives a must?

Cheers,

David (jdb03)