Using Sharkbite Connectors Caution!

I just redid my shower/tub valve and did not want to solder connections because of space limitations. Guys at Home Depot were high on Sharkbites, which are kind of expensive, but I went for it.
First caution: They can be removed and reused, but the process is not as easy as they say. Second caution: When attached to a copper pipe, they are indeed water tight..no leaks. BUT, they do not lock onto the pipe and the pipe turns freely. My biggest problem with this was screwing on the new tub spout. There is hardly any clearance to hold the pipe from turning, so when you try to attach the threaded spout, the supply line turns as you are threading on the spout. I finally wrapped duct tape to the supply line and held it tightly so it would not turn, and just cut off what I could and stuffed the rest in the wall.
I have read that there is liquid solder which does not need heat, but my choice would have been a compression fitting for the spout line.