I got one a little while back. It cools very well - it's expensive for what it does, but it looks cool in your case. You can change the colour of the lighting on the display and it shows a large type readout of the current temp.
It's very quiet, occasionally it might gurgle for a second or 2- I fitted 2 apaches in place of the single stock fan and can hardly hear them over gpu fan, I can't say what the stock fan is like as i didn't use it at all,
It's good for being able to fit RAM where you want it, so no slots blocked.
I just left the stock paste on it which seems good enough, I haven't felt compelled to take it off and apply something better.
Annoyances: it has a beeping alert that goes off each time i cold boot my PC - it seems to beep until the temps go above about 18/19c, I also get a fan speed warning when it powers on - I just need to get around to disabling this but added to the beeping noise is a bit annoying.
The pipes aren't that flexible, I think you could have problems trying to fit one onto a SFF build as orientating it and having it sit over the socket correctly would get much harder the less space you have.
As for temps it outperforms my old Thermolab Baram with 2 apaches by a fair bit, I can get better OC results with this fitted as it keeps temps lower under load a lot better.
I was looking at getting an omni as well to have an easy dual loop setup, but considering the current uncertainty about future support with the coolit/corsair partnership and the possibility of no support for future cards i've decided against that.
