Should I put Quick Sun's Radiance (320 Haste) in the yellow sockets, or Fierce Vermilion Onyx (80 Strength and 160 Haste)?
So should I max out Haste as much as possible or Strength for Raiding? (See progression)
And what about Red and Blue Sockets, should I go for more Haste there aswell, or get some extra Strength?
After checking many websites i'm not completely sure what to do, so.
sim it with str gems and then haste gems... it's pretty close when you're 490ish
tbh it's personal preference IMO, sims will show the DPS very close whether you go haste or strength. I generally roll with str gems (mostly because i'm unholy for a lot of the time) because any sort of movement fight/time where you're not hitting the boss (which does happen in some fights this tier) devalues haste somewhat. However, sims will generally show haste having the slight edge so most semi-decently geared DKs seem to gem pure haste and it does feel better having more attacks/less times when all your runes are on CD.
try it and see, you won't break your DPS either way.