I have only used the stock spring, and I have never had any issues at all. I do lube it to smooth it out and quiet the "twang" noise.
ArmaLite AR10 buffer springs (EA1095) are the ONLY spring to use in ANY .308 AR in my opinion.
Wolff doesn't make a .308 buffer spring, period. And I don't believe that the Springco springs are designed for .308s either.
Thanks Slash, I guess the standard 308 buffer spring is different spec than a standard A2 spring. I asked this question in the Variant section and got no reply. Thanks Again.

Originally Posted By REARSPROCKET:
Thanks Slash, I guess the standard 308 buffer spring is different spec than a standard A2 spring. I asked this question in the Variant section and got no reply. Thanks Again.

Yes,very much different.
Some info: