I guess I'm lucky, I've done all kinds of "terminal hacks/tweaks" and run a bunch of "tweak apps" (better touch tool, total finder, hyperdock, coolbook[and I'm running very low voltages], probably more but those are what I can think of; all of which I use the beta/alpha if available), download 10.6.X updates as soon as they're seeded to devs, use beta/alpha versions of apps if available, blah blah. And everything just works, I can honestly say I've never had an issue that was "worse" than say Chrome Canary not closing properly and needed to force quit; no kernel panics or anything. I shut it down each night, and when it's sleeping during the day just open the lid and everything instantly works. I really couldn't be happier with my MacBook.
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man I have, EVERY clean install, had my computer go crazy from just installing different services or open source project apps needed for other apps to organize other apps. I use onyx to keep things clean when I get gigs moving about but... man it's like a guarantee. I'm replacing my HDD as it has problems and I'm hoping those are it.