Don't buy cheap no-name chinese quick links. I got some that didn't click-in to hold the link in place. I got my money back on e-bay.
Wipperman links are the best, but the cheapest price I've seen is two for $30 at Bikesmiths.
Now that I'm using Campy 12, there are only two choices - the KMC 12 link or the SRAM eagle 12. The latter fits the best. I got four of those for $15.