I’ve just replaced my chaintool, I have had the Park tools CT5 for a few years and recently it’s just been a pain in the arse. The pins flaired out (went through 2) and the T-bar bent when applying pressure. Also, the “shelf” where the chain sits had bent as well, so some chains couldn’t go in.
I had to get a replacement when it bent to unusable proportions when trying to remove an Octane One Single chain. I’ve just bought the X-tools 18 piece tool kit and the chaintool just worked straight away on the very same chain.
Basically, for me the CT5 was a little too small, and so couldn’t get a decent amount of torque without bending the t-bar.