My experience with my two TQs has been positive.
I'd start by asking what type of shooting are you going to do? I only do square range stuff at Quantico out to 1,000, no running around, barricades, etc. It could make a difference if you want a quick attach system.
The TQ uses the LaRue brake and is screwed onto the brake. It has a double shoulder design along with a lock ring. Obviously, since it's made by LaRue, it has been tuned to the tOBR (or vice versa). As you may know, the tOBR has a dual gas block design with two differing sized gas ports, one for suppressed (smaller) and one for un-suppressed (larger). In my tOBRs, it's run flawlessly with almost negligible blow back.
My TQ does shift POI by 1/2MOA lower, but it's repeatable. I dial in an extra 1/2MOA and I'm good at any distance. It's also consistent, when I remove and reinstall the TQ, it's always 1/2 MOA. I get about an additional 25fps when using the TQ and it actually tightens my groups by a 1/4MOA.
I can't speak to db as I think they are all pretty close, but the TQ has a nice tone to it. Here's a short video attempting to compare the Surefire on my 260 to the TQ on my 260 gasser.
I've shot the TQ for about 1,000rds with no issues, as I have with my Surefire. I got my TQs for killer pricing, $499 and for the money, I think it's a good can for what I use it for. Hope this helps and ask questions if you need to.
One of the rifles on the line at Quantcio R4 with the TQ.