I like Sharkbite fittings! I would only use them where they can be seen - I would not put them behind a wall. They have been around for some 15 years and have a reliable reputation. They can be installed on wet pipes, and are removable. But, instead of using a hacksaw, a little pipe cutter with a good blade leaves a fairly clean cut - there shouldn’t be any burrs.
This Sharkbite fitting replaced a leaking saddle valve. I was stressing about how to solder in a new piece of copper in this tight space. A friend told me about the Sharkbite solution and I was sold.
Here is another Sharkbite fitting that is like a saddle valve. This is the 1/4" supply to the humidifier. I will never use an old-style piercing saddle valve again.
A plumber installed this ^^^ water heater, because we were replacing an electric one with a gas heater. I did a gas water heater replacement in another house - not bad to do. Something I learned is that the copper piping in and out of the water heater should have dielectric (?) fittings to prevent an electrical current from running through the connections. Otherwise the connections will corrode and fail. See the silver fittings on the top of the heater ^^^.