I always advocate the use of a divider and tight timings so something along the lines of the Corsair 3500LL Pro, Mushkin Redline XP4000, OCZ Plat. 4000 EB all of which I beleive use Infineon CE-6 RAM which will do 2-3-2-5 @ 200mhz but also clock up and are guaranteed for 250mhz.
My OCZ in sig will actually run 270mhz 3-3-2-5 and I'm sure could do 275mhz at the same timings. A gamble but a whole lot faster than that RAM at the same speed. For a budget option, the OCZ Plat 3200 CAS2, G.skill ZX etc (that are rated for 2-3-2-5 @ 200mhz) are unbinned CE-6 so they might clock, they might not but will still keep timings tight at lower frequencies.
Now given my statement, you are wondering why I am not following what I preach (not using a divider with tighter timings as my memory is capable of it). Well I clocked my processor to 2.8ghz (first ever one to reach this) and I didn't want to touch it as it is stable and putting it on a divider would require a full stability test again which I don't want to do, otherwise I too would be running probably 210mhz 2-3-2-5 1T.