Of the two, Dominator for sure.
Can't say I've had any problems especially in the capacity I have it in and the system it's being run on!
Dominator DDR3's fins can be removed also if that helps
Good to hear you're not having problems with yours (yet). I'm just saying, in my experience Vengeance is not good memory and I'd advise almost anything else.
Also a nice touch.
With Vengeance the plastic heatspreader often just falls off, both sides come apart to reveal the green PCB memory underneath. At least with Dominator you can remove the fins and leave the rest of the heatspreader on so it still looks decent.
One thing to note, the Vengeance fins aren't plastic, they're alu alloy. But still, a bit silly looking considering the restrictions they could put on a big CPU heatsink.
They're definitely not plastic...
Don't Corsair do the LP stuff? More practical I would have thought.