I believe you need both a pure bt to learn the feel of true bt and a thumb trigger to shoot if you feel the need.
I love my Carter Fits me Too thumb trigger but I had to learn bt on a pure bt.I used the Tru ball ultra 3 to learn with and have recently (today)picked it back up as my main release due to some of my old target panick setting back in.
This release is very affordable at $60-$70