After using the seat for a couple days, I have few more thoughts for those considering the Frontier:
After taking it in and out a couple more times, it is easy for me to get a rock solid install with the lap-shoulder belt using the recline trick in my '05 Honda CR-V. If I'd intended for it to be a dedicated seat in my car, I'd be happy with it. It takes no more time to install than it takes me to install our FF BV, and threading the lap-shoulder belt through the belt path is easier (and less dangerous for my knuckles).
My tall 4yo daughter loves the seat. I like it too, but I have a few minor quibbles.
(1) The door-side cup holder can't completely unfold because of the way it fits my car's rear seat. No problem, because the center-facing one can unfold just fine. But the door side cup holder partially unfolds on its own because of how my car's seat presses on its base, and that is aesthetically annoying.
(2) Use of the recline block forces the seat to hang over the edge of the car's seat. No biggie in my car, but if rear leg room is limited, it may be a problem.
(3) The armrests are a bit wiggly, and I wonder if they're sturdy enough to hold up to years of use. I'm concerned that if they're leaned on frequently while entering or exiting the seat, they may eventually break.
(4) When installing as a harnessed seat, you have to be careful to make sure the recline block is forward. It easily flips back on its own when the seat is lifted. I suspect many parents will accidentally install it with the recline block in the booster position.
I bought the Frontier intending to put it in my husband's '96 Prelude, but I couldn't get a satisfactory install in it. So though we like the seat, I think I'll be sending the Frontier back and ordering a GN for his car. Bummer, because I've always loved the way Britax seats install, and the pink and black Frontier is way cuter than the GN.