Obviously there is a wide range of opinions on this subject! In the end, only you can make the right decision for your family.
I'm not sure what's so bad about the Ultramat compared to other protectors. Of course if you're against all seat protectors, then yeah, other than the fact that it's cut just right to fit a rear-facing Radian, it isn't somehow magically different from most of the others on the market. It's very thin and flexible, much like a towel actually, and it doesn't change my installation at all. The Prince Lionheart Stage 2 seat saver is evil, though. There are a few other brands with a similar design and it's nearly impossible to get a seat tight on them. I'm extremely suspicious of the new Britax seat protector, too, but I haven't seen it in person. It looks too similar in design to the other stiff pan-like protectors on the market that are so horrid.
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