But it's REALLY heavy and seems pretty stuffed! So, now I'm looking at the 300 because I want the option to leave my 70-200 attached and I really think all I have in the 200 may be a bit too much weight for the bag.
Just travelled to Alaska with my 200, and found that it was great in most respects. I took it on water taxis, long hikes, air taxis, long car rides, short hikes, etc, and it was fantastic.
My gripe is that, with only one strap, if I hiked over a mile with it, I would get a sore shoulder/back/hip. This was not the case with my 2-strap bag, since that distributed weight more evenly. The 200 has a cross-strap that helps but it's not perfect, I still had to tweak my posture on longer walks to compensate for the single strap. If you're going to stuff the bag full, think about a 2-strap bag as an alternative, if you plan to do a lot of hiking.
For short trips, it's awesome.
Also, I'm not sure why one strap is an advantage to anyone, personally I found myself taking it all the way off when I got stuff in/out of it, so I didn't think the "sling" feature was that helpful, but that's just me.