I plan to get some quality 1333mhz ram for it. Hoewever, when looking at the prices, I noticed that the 1600mhz stuff is only about $5-10 more on avg. G.Skill has 3 sets of dual channel(2x2gb) 1333 for $50, $55, $60, being [9-9-9-24], [8-8-8-21], [7-7-7-21], and also 1600 for $60, $65, $70, being [9-9-9-24], [8-8-8-24], [7-8-7-24].
My question is: How much can you tighten the timings for 1600mhz when underclocking it to 1333mhz? IE: Is it worth it to get 1600mhz instead of 1333mhz, underclock to 1333 and tighten timings?
Tightening latencies depends on the actual chips on the RAM. I've found that 1600MHz gives me some overhead on the RAM dividers when OCing. Whichever you decide upon, get the ones with the lowest latencies you can afford.