i use a thumb release and have for years. spot and stalk and tree stand. having the ability to leave it on the d loop is essential in my opinion. hangs on the d loop in the tree and for stalking, the activation bar hooks onto the cables, so theres no way it can fall off, sits snugly and is in the perfect position to grab in a hurry. i use a truball max3 hunter, which is considered an 'entry level' thumb release, but its got adjustable tension, the bar pushes forward instead of pulls backward, fits my hand and is a caliper style. all things i wanted. i have 2, just in case.
going to a thumb release helped my shooting quite a bit. my form improved by becoming more repeatable and relaxed, my shot execution got smoother, i didnt just get the pin on target and slap the trigger. i became more methodical and precise.