My son ran my old CRT 727 after I switched to a powerglide. He loved the transbrake but he only had an 8 3/4 rearend in the car so it had limited use. With the 5600 stall converter he ran almost exactly the same with or without the transbrake. Honestly if you don’t have a valve body I would get one with a transbrake then you can go either way. Plus it probably holds its value better.