I always used the quest compression fittings, but the sharkbite fittings work as far as everyone says. The best thing is to use a PB to PEX fitting and crimp it. Now there has been rumored to be troubles with one of the bigger PEX brand of fittings. I have used PEX fittings and not had problems. I think I would rather use the PB to PEX fittings and change anything that would cause major damage in the event of a leak. Some of the problem with PEX and a lot of plastic pipe is if it is strapped too tight. It must have room to expand and contract, a lot of room. If the pipe is stretched it could pull out of any type fitting. You should never use a brass compression fitting on plastic pipe unless it has the plastic ring. Some of the shark bite fittings say to only use them on copper, make sure you use the correct ones.