I like mine. The one I have doesn't allow for adjustment of pitch to tune to a specific instrument but it's great for getting everybody at least into ballpark range. You'll probably have to tweak the specific tunings on your strings a little bit but not much (assuming your instrument is set up OK).

I can also tune by ear reasonably well. I think having the tuner actually helped me a bit with this since I could be more sure I was learning to tune to the right note rather than somebody else's alleged "A" or whatever.

WLD is right; they do cut down on arguments. Everybody gets the same notes.

Mine is fourteen years old and still works just fine, too.