As usual - my open-ended question has yielded volunteered information that I couldn't have hoped to get by asking pointed questions (e.g. - I did not know what I did not know).

I can tell you my Kramer $800 with Floyd Rose system and whammy bar stays almost perfectly in tune, while the remainder go out within minutes - but it could very well be I overwind the strings - and all those other things Mario told me to rule out first, I don't know how to do that.

nonetheless - I will pick and choose from the comments above that get the most consensus from our most knowledgeable contributors. The newer guitars I've purchased (there is a 1 - 2 year lagtime in acquisition and frequent, consistent play with me - yes, it's a little embarrassing to admit) don't come near the Floyd Rose. But as I play them more - I'll first begin paying attention to all the things you've pointed out on this thread to figure out if the machine heads need replacing.

Thanks again for all your great responses.