Lane wrote:
I'm going to be watching the answers on this one, I've worried about it also
and ended up using threaded ones.

I did all the plumbing in this house. All the shutoff valves are ball
valves with teflon seals. (Look into the valve. Teflon seals are
white.) I soldered all the connection and had zero leaks or failures.

Clean both the valve and the copper pipe with steel wool, apply flux,
fit together and solder with a propane torch. Apply heat to the joint
area until the solder melts on contact with the joint and flows into it.

When soldering, cleanliness is not next to Godliness. It's way out in
front.

Ted