Don't have any experience with a hexagon. In general, the ovals shed wind better and the squares are A LOT easier to set up.
I just set up a Kifaru tipi for the first time this past weekend in a blowing snowstorm while wearing snowshoes. It was a 12 man and I had the directions printed out. It was pretty straightforward, with no missteps on my part. I could see how with practice it wouldn't be that big of a deal to throw one up. It took about 45 minutes to get that big daddy up under those conditions though. You have to get quite a few stakes in to get the stability and geometry you need.
On the other hand, for smaller shelters and taking down / putting up every night, I think I still prefer square, which I've got a lot of experience with (megamid, sl4). Put in your four stakes, throw up the center pole, done. No setbacks to measure, no walking back and forth from side to side to get your setbacks even, etc. Maybe 2 minutes. From there, you can add additional perimeter stakes if you need or want them, but you can do it at your leisure from the security of a shelter that's already set up.
