Had mine for around 6 months. It's magnificent.
Sound stuff: The word that springs to mind when I think of it is 'size'. Actually, 'SIZE'. It makes things BIG.
Coloured, yes. Running it cooler on the way in helps if you want less. If you want more, there's plenty there.
Note also that the MS encoding is done before the gains, so if you switch to MS you instantly have more tube colour. Mid signals tend to be stronger than side in most cases of course, so push the tubes that much more. I use that aspect the MS mode for bringing out buried vocals, for example - very useful, it's essentially another sonic option.
The compression action itself is great - I could write an absolute ton here but it's been a long day. But in short, it's f#cking great.
Interface stuff: The variable linking is brilliant - the only thing I really missed about selling my API 2500 was that aspect, and this does it even better. I run mine in vari mode practically exclusively. Set link to 100%, set one channel to 1:1 ratio, use other channel to set compression (timing/amount) for track, match on other channel, play with linky linky. When turning up the second channel's ratio it digs in harder, but when set to 50% link you'll get the same amount of compression (hope this makes sense). I mention 50% link as I tend to be around there most times - it just sounds massive. If I need to keep the centre more solid I'll compensate elsewhere, or do stronger link with a lower ratio.
Overall, it's really very difficult to leave it out of the chain. It might require some compensatory moves if it gives a little too much colour, but for the stereo manipulation, general sound, and compression action it's superb. Basically it gets left out on some heavily processed already-coloured/saturated mixes, for dead/lifeless stuff it's almost like cheating.
Make sure to run it cooler than you might expect - RTFM and do what Jakob says. He knows a thing or two about audio gear, that bloke