Odyssey plus one Radian install question

I have searched and found a lot of information but haven't found conclusive info either way. I have also read this: http://carseatblog.com/8090/2011-ho...ids-carseats-review-with-tons-of-pics-videos/ and I can't tell if the YES it installs but has a lot of rotation means it is ok or it isn't safe to install it that way.

I have four kids, two "bigs" that sit in the third row of my 2013 Odyssey that I just got and RF twins that I was planning to put in one captain chair, the plus one seat, and remove the second captain chair so the bigs can get in the back row easily during school pick up. And because of the weird crevice, I can't get the Radian RXT to install securely by my standards. I can get the seat to not move much, but it slides around on the back of the base quite a bit, even with the angle adjuster. Also based on the above article, it looks like I wouldn't be able to put in a Britax, which would be my second preference.

So my questions, how much movement is "ok" for the top of the car seat to move? There aren't any good tether anchors for the top of the seat, but based on another thread, someone called a car seat company and they said it was okay to use the seat anchors below the seat that the car seat is installed in (in the Ody, they slide on this track to go into wide mode). Even with the top tether, I get significant movement. Also, has anyone actually gotten any other seats besides the Graco My Ride RF installed in this seat? I am feeling very frustrated as I currently have the twins in the captain chairs, which means the bigs have to climb in under it and through the middle which doesn't work long-term.

I realize that you may have found your solution already in the other thread about the new generation Britax (which I'm happy to hear installs well rear-facing in the center seating position of this vehicle!) but I wanted to address the Radian issue for the next person who has the same question.

As you can see from my blog review, I tried *many* different seats in the current gen Ody. The movement that I found with the Radian on the center multi-function seat was unusual. I don't remember how I discovered that it made this movement (I don't normally try to rotate seats when checking for tightness at the beltpath) but I did notice this particular movement and I wasn't really sure what to think of it. Nothing in my training or experience tells me that this is bad or wrong but it's definitely not typical either. I still don't know what to think about it. Personally, I don't like it but that is strictly my opinion. I can't say it's bad or unsafe.

Anyhow - here's the video. You (or the next person with the same question) can decide for yourself how you feel about it.

[ame="http://www.youtube.com/watch?v=DFtFVQ2c2VM"]Questionable installation of RadianXT in 2011 Honda Odyssey - YouTube[/ame]

http://youtu.be/DFtFVQ2c2VM