Warranties for Black is great, except Not that important as warrantee period is based on Many factors, of which reliability is often not the leading factor. Normally for the longer warrantee you just pay extra.
1)..When I was in TV repair, I could buy a CRT, sales man placed ON desk, cost increased with warrantee I wanted to pass on - EXACT same CRT - How long it would really last HAD nothing to do with the period of time increasing the warrantee period WOULD NOT increase how long it lasted.
2) Newegg ratings:
... Samsung 1 TB F3. 2056 Responses: 15% 1/2 egg ratings vs 81% 4/5 ratings. (Winner)
... WD Black Sata III (6) 1738 Responses: 19% 1/2 egg ratings vs 73 % 4/5 ratings.
3) F3 seems to be more often the recommend choice between F3 & WD blacks. I was looking around and found that Anandteck used the F3 as the recommended drive in their mainstream High end Build:
http://www.anandtech.com/show/5196/holiday-2011-mainstream-high-end-buyers-guide/3
4) Not really sure which one has the Highest performance (ubercake is Correct - SATA III (6) is just a marketing tool), But probably so close that the user will not tell the diff in real lif usage.
4) Back to warrantee. When one of my drives fail, I do Not send back, I take a Hammer to it - Have data on it and if I can not ensure data can NOT be retrieved, It is NOT going anywheres. It's always a hassle to RMA a drive, so I tend to pick which I THINK has the least likehood of failing.
WD blacks use to be my drive of Choice, emphases on PAST tense.
PS: Curcial M4 is an excellent choice. NOTE: I have 2 128 gig M4s, two 128 gig 830's and two 120 gig Agillity IIIs