Recevied my SL1 in the mail today. I went outsideto set it up right then and there.
Being that it was my first time using a 1 piece "Y Pole" design tent, it took me 10 or 15 minutes to get it sorted out. As soon as I got a feel for it, it went up in a breeze. I put the rain fly on it as well, grabbed my thermarest (full length for my winter trip) and my sleeping bag, threw it all in there and climbed in.
I gotta say, I'm pretty pleased with how I fit in there. One thing I did make sure to do was stake out all the corners, and paid special attention to the sides so I got full internal floor space in width. There was enough room for a 6'5 guy stretched out w/o touching the sides. I wouldn't be able to fit much other gear in there with me, but the vestibule *should* be able to fit my pack (Nimbus Ozone....new pack, so it's on the way) if you were to get a bit creative. In the warmer months I plan to put my backpack under my legs when I use my 3/4 length sleeping pad.
Overall, this tent fit my expectations fully. I was looking for a good lightweight tent, that would fit my size. This tent fits those expectations.