I'm not a pro on laft rafts, but these folks are : Life Raft and Survival Equipment: Life Rafts, EPIRBS, PFDs, Safety Equipment
Give them a call, they are very helpful. I understand that self-righting is a bit of a fairy tale. Easy to right is more accurate.
We own a couple of different Winslows and I like them. You can customize for your needs. If you really want a raft that you can survive in for a week, you're going to literally need a dolly to move it. 100 lbs for sure, maybe more. You'll need a double insulated floor, ramp access, upgraded sea anchors, windows so you don't too sick, etc. Most important, you can't rely on retrieving your ditchbag, so you'll need a week's supplies pre-packed inside the raft, which they will do.