Thanks for the welcome guys.
Like I said, the guy I work with loves the ropegrab. I think the one he uses is too small, the lanyard is 16mm and it doesn't leave much room. For me it's also my way of doing things, one example, when blocking I'm use to feeding line out one handed while leaning back, if I tried that with the grab, I'm afraid it would release my lanyard so quickly I'd be on the ground. This may not be the case, but it's my main apprehension.
Habit can be a good and bad thing. I always put my gear on in the same order (something I learned while commercial diving), if you're missing something you'll know it. A lot of guys climb with their saw attached to a hook and use it free hand in the tree, mine is always tied with a 3' piece of rope to my right side. I was trimming a tree without gear on one day, just went up on a ladder and climbed in (retopping a low hedge). I ended up throwing my saw out of the tree to quickly grab a top! I didn't even think about it, just habit.
I like trying new stuff though, thought about starting a new thread on that, as we all do things different according to the types of cutting conditions, which vary immensely looking at the photos you guys post. Learned spurless only a few years ago.