We have a Nuna rebl. I love it, I find using the one in mums car (that doesn't spin) a real pain with a heavy 2 year old.
People said I'd miss not being able to click the car seat on the pram chassis, or carry dd in the car seat. But I'd had a c section, I doubt I could have carried the car seat and nearly 9 lbs of baby for a while anyway!
The only thing I didn't like was that even though there are 7 recline settings, when dd was newborn I didn't feel like it reclined enough. She always seemed comfy though, and the shoulder straps are quite padded, if positioned right over her shoulders they came under her chin which stopped her head falling forwards.
She's very tall for her age and still seems comfy rear facing. I think we'lll definitely get our moneys worth out of it too, there is still lots of growing room.
Another thing is Nunas customer service, I found them amazing when about a year ago, the company - Which, found that the first car seat they made didn't pass their levels of testing. It passed all the EU regs etc but when tested at higher speeds, in an impact the seat unit came away from the base. I contacted Nuna who were fab. They had already designed a second model which did pass the higher testing. They offered to deliver a brand new car seat (the new model) and collect the old one (completely free of charge), or offer me a full refund for me to buy something else. We got the new one because I couldn't find anything I liked as much.