Samsung 840 Pro SSD 512 Gig
I have a Samsung 840 (not the pro) in my 2009 17" MacBook Pro and it works great! I went with the non-pro because its only a 3G max speed and I would lose the performance gain that the PRO can provide. I do have a 256GB PRO in a '12 mac mini and it run great. I did not upgrade either one's firmware. Although I put them in a USB enclosure attached it to my PC to see what rev they were on (3B0Q/6B0Q - which is comes on all retail version and is the recommended rev as far as I know).
As with most things if you don't have any issues with it don't upgrade the firmware so, the fact that they didn't have a firmware upgrade option on OSX didn't bother me.