I use an Alpkit Hunka, normal size, I keep wondering if I would do better with the larger size but haven't decided yet?
I had my Hunka modified, just couldn't get on with it as it was, I'm no good at wriggling in and out, so a friend of my wife fitted a 4' waterproof zip along one side, now its transformed, so much easier to get in and out of and so much more usable. I tried putting my Thermarest Prolight mattress inside the Hunka but not very satisfactory, so now have it under me, much better.
I also carry an Alpkit 3.5 tarp with me, plus a 6' x 4' groundsheet as well. I used to erect the Tarp as an open pyramid, but recently I haven't bothered. I've now had two nights where I've just put my rucksack down lengthwise on its back, tucked one end of the Tarp under it (the furthest away point from my head) and kept it rolled up and ready should the weather deteriorate. I haven't had to use it yet but my plan is to grab at it behind my head and roll it over the top of me. I'll then just use two pegs to pin it close to me, I only need it to cover my head and torso. I haven't perfected the idea yet but if it works fine I may stick with it, but if not I'll just go back to erecting a pyramid tarp again.
I want to try this out because for me the Hunka is great for stealth camping, very good when I leave a pub at night and don't want to walk very far in order to sleep.
I also own a Snugpack Stratosphere, which I've only used three times, It's OK and it's well made and it has a raised area for my head but I also took the Tarp with me each time as well. When I weigh the Stratosphere, the Tarp, and the groundsheet together its just as heavy as my tent. If I get the chance this year I'll try to sell it.