I run TriggerTech is 95% of my AR's and have been very happy with the product and customer service, that being said I have worn a couple of them out but when you actually do that TriggerTech takes really good care of you.
I will be picking up a single stage version. There is absolutely no other trigger on the market that comes close to how clean and consistent the trigger break is on TT's, it's just the perfect trigger for Long Range Precision shooting in a AR IMO.
Every time I let someone at the range take one of my rifles for a test drive it's the first thing they comment on and It usually goes like this.."Holy shit! That's a nice Trigger, oh looky there all my shots are in the same hole"...
The extremely short and light first stage does seem to throw some folks off at first, mostly because their used to the Geissele style 2 Stage with the heavier first stage pull and lighter second so I think this single stage TT Diamond will be a well loved especially for the folks who primarily shoot bolt guns.