In reply to neuromancer:
I skied 95 for quite a few years and never really felt that I need to go much bigger, saying that I have been very lucky and been asked to test and review some skis over the last few seasons, I have been given lots of different sizes to try.
Out of all of them so far my favourite is the OGSO 106 fully rocketed model, its not just the size its the shape and flex, I just find it a real fun ski to ski. I ski just about full time in the winter, and when not testing its my go to ski for everything. Its light for a 106 ski but obviously still heaver than a skinnier equivalent, but I am happy carrying it for the fun it gives me on the way down. I was a bit worried as it was fully rocketed and a medium flex it may struggle on the steeper lines, but no I love it.
Mainly the reason you see people on fatter skis, is for most snow types the extra float makes it easier. I haven't found a down side of skiing a 106, no situation where I wished I had thinner skis.
For me I think anywhere between a 95 and 106 is a nice sweet spot for one ski to do everything, with a 95 being a bit lighter and a 106 being a bit easier to ski. ether side of that and its starting to get a bit more specialised for example I am currently testing a 86 underfoot version of the 106 ski and I really like it, but it is harder work in the deep, but I think it will fly on good spring snow. I think getting a flex and shape you like is just as important as size underfoot.