FWIW i like it very much so far. I am doing the demo right now.
I just finished demoing the McDSP De-esser and although I didn't spend _too_ much time using it, I frankly was underwhelmed.
I am demoing the Eiosis E2 right now as well. All I can say about the Eiosis at this time is it's not (for me) a product that I can 'quickly' find desirable results with. I will be spending more time with that particular plugin before I dismiss it though.
The Sonnox SuprEsser is obviously well-programmed and well thought out. I am able to get very good results quickly and as I continue to tweak its parameters I think I can even improve its output. It operates very transparently if you wish it to. No loss of important frequency response and no squashing entire bands of frequencies just to perform its task.
Obviously it's a complicated plugin with many features though; I don't want to make it sound overly simplistic; but the bottom line that has impressed me so far is how quickly I could get rid of sibilance with very little damage to the source.
I need more time with both (well actually all 3) plugins before I can make a final call, but at this point it looks as if I will purchase the Sonnox. It's niiiiiice.
JD