I don't love the Radian, and I think at this point that I just tolerate it and keep it because of the higher weight limit for rear-facing. We haven't been using it very long, so maybe I'll grow to like it more.
I have a 35 pound 2.5 year old. I personally would not forward-face a 2.5 year old if I had other options open to me, so I was faced with choosing between a Radian, a My Ride, or a Complete Air in my car to rear-face past 35 pounds. I'm not a fan of the Complete Air. I really like the My Ride; I have one in my husband's car, but I don't like how it installs in my car. So, that left the Radian.
I bought a Radian XTSL. It was a bit of a pain to install. It's very difficult to adjust the harness while my son is in the seat. When I'm in the front passenger seat, it's not very comfortable sitting in front of the Radian; it takes up a lot of room front-to-back in my car. But, it's the seat that works to keep my son rear-facing, so I tolerate it. I've been considering buying one of the new Evenflo seats that should be coming out this summer with a 40 pound rear-facing limit and using that until he hits the 40 pound limit then switching him back into the Radian. That's probably ridiculous, I know.
In the end, the Radian is very comfy for my son and he loves it, and I'm glad he's rear-facing. It has a 45 pound rear-facing limit and a pretty tall shell, so it might be the only seat besides the 80SL that will get my son to 4 years old rear-facing. I'd still say that I'm happy with my choice of the Radian, even if I don't love the seat itself.