I do own a pair. I've read a few short reviews on those (magazines written in french). They were described as a good pair of intermediate level ski boots IIRC. I did find them very comfortable during the first few days I used them but the inner boot seems to have "compressed" (for lack of a better word) pretty quickly (or I just got accustomed rather quickly to my new found comfort...). They are not "that" warm though but that may be a personnal thing depending on what kind of socks you're wearing, blood flow in your feet, etc., etc.
All in all, I'm pretty satisfied with my purchase of the Proton 8 boots, as they are not very expensive and were a huge step in comfort from my Rossignol Power 90. Take note that I weigh around 160lbs and am maybe a level 6 or 7 so YMMV.
FYI, here is a description taken from an online gear shop:
The Dalbello Proton Series was developed for accomplished and athletic skiers seeking power and stability with unsurpassed snow feel. All Proton's feature the "NewFit" shell last with performance tapered rearfoot contouring for precise and accurate foothold. The "relaxed volume" toe box provides all day comfort and warmth.
Developed for athletic intermediates and advancing skiers who demand quickness, precision, and comfort. The P 8 is a high tech, versatile performer that excels in all terrain and conditions.
Hope this helps (at least a little)!