i'm running Win ME on my overclocked Tbird setup. my 900 Tbird is oc'ed @ 7.5x145fsb and it's stable as a rock... Win ME hasn't crashed once in the past week that i've run this setup... went through all sorts of stability tests and came out fine...
i think Win ME deserves a lot more credit than people give it... bootup is a lot faster than Win98 as well, and i don't see any difference in gaming... maybe the loss of a few fps, but that is insignificant when your video card is fast enough to churn out 100 fps in a game...