I love ECM, it turned me on to a lot of musicians I would have never heard, before, including Terje Rypdal. Then again, I love washy, reverby stuff, so that's probably why I like the label so much.
I wonder if this is a more recent thing, though. There ain't nothing tame at all about David Torn's Cloud About Mercury album (with Levin, Bruford, and Isham) - that album has some serious balls in parts, and those first Pat Metheny Group albums were nice and clear,as was Bright Size Life. Granted, there's nothing gritty about PMG, but I've always liked the clarity of those first two albums of theirs on ECM, the ones with Mark Egan on bass, who still gives me a musical woody when I hear his playing on those two, as I love that gooey creamy fretless tone that people either seem to love or hate. I just can't believe he was getting those sounds out of a P bass.