I like them all

my group is a druid, lock and shammy for my dps and right now have two set ups for my lock and druid.

first key up my lock does his dot rotations + spell rotation
secound key i call my base key where he just does immolate, conflag and incerate.

I find when im doing heroic boss the lock benifits more from the secound dps click key. When it comes to icc heroics and raid boss the first dps key gives him more of a dps boost.