Fed up with cheap multi-turn angle valves

Hi all, I have a 20 year old house with copper pipes and the handles on 2 undersink angle valves have broken so far. I googled angle valves and some will say that we ask a lot of angle valves, not turning them for 10, 20 years and then expecting them to turn off with little effort. Probably a lot of truth to this but in any case I'd like to replace some of mine with 1/4 turn units. My understanding is that the 1/4 turn sometimes do not fully turn off due to tiny defects in the metal but they are less likely to get stuck and break. Problem is, the Brasscraft ones the home improvement center carries don't work with the existing copper ferrule on my pipes (I'd rather not remove the existing ferrule). I'll probably go to a pro plumbing shop. It looks like the Watts 1/4 turn will work with existing ferrules. Is this a good way to go for replacement? I also need a 1" gate valve that has failed (main house shutoff). Is there any preferred brand? Also, I read some instructions on replacing angle valves and it suggested 2 turns of Teflon tape on the male threads. Is this a good idea?