I use the W&T. It's the same as the W&T2, except it uses a webbing for the shoulder straps.
I only use it when I need extra weight, like diving my neoprene drysuit. It carries weight wonderfully. I load it with about 25 lbs. and can walk around with the weight all day. I like it because like another poster, my posterior isn't enough to hold a weight belt up.
I also like the fact that I can put weight in the W&T and use it as nonditchable. What I mean is I put about 25 lbs in the W&T and about 6-8 lbs. in my weight integrated BC. I consider the BC weight as ditchable. If I dropped the 25 lbs I'd be a rocket. In regards to if it were under a BC it's be nonditchable - you wear the W&T low on your hips and it is under your BC, so you could ditch it if necessary.