Need opinions for boosters

[MamaKto3]

Hi all
One would think that the child safety people would make it easy to sort out the differences between all of the choices, but, nothing in life is easy, esp with kids! LOL
Here's my question:
I drive a Honda Pilot with my 3 kids. DD1 (4 yo) is in a Britax belt positioning booster, and does fine with it. DD2 (2 yo, ~25#) is in a Britax RA, fits nicely, and considering how petite she is, will probably be in it until 4 or 5 (at least). Her twin brother (2 yo, ~37#) is also in a RA, but will soon outgrow it.
The reason I didn't bother listing DS's height is that, like most toddlers, he's pretty disproportionate. Legs are short, top is not. He's big across the chest (when he's wearing his bulky winter coat, I can barely buckle the chest strap). Top of his head is just past the top of the seat, ears are about 1" below the top. He really still needs a 5 pt restraint.
I'd like to get another Britax (love them!), but I'm not sure about what to get. I'm pretty sure that the larger convertible models won't fit with the other 2 seats, and I'd prefer not to move one of the kids to the 3rd row (just not old enough yet).
Does anyone have a suggestion? Like I said, I'd prefer a Britax, but would consider others. The budget allows about $300 or less, but that's a squeeze. Thanks so much for any opinions or input~
Elin

[Scatterbunny]

The Sunshine Kids Radian is very narrow (17 inches), and it harnesses to 65 pounds, but it has installation issues, so I'd only buy it if you can try installing it before you make the final decision, or if the store has a good return policy.

Another option would be to give up the RA for the 2yo and put her in a Graco CarGo (because it is also very narrow). It has EPS foam and deep sidewings and good padding if you go with any of the front harness adjusting models (a must), also very tall top slots (as high as a Britax Marathon). The 2yo would be fine the the 40 pound weight limit, and that would allow a precious few more inches for brother's seat, and you may be able to go with a Marathon for him.

Any of the other higher weight limit options are much wider. The Cosco Apex is almost as wide as a Regent.

I think your 4yo is in the best booster for three-across situations (Parkway, right?), so we can really only try to figure out ultra-narrow options for the twins.

[Joolsplus2]

I knew a mom with 2 Marathons and a Roundabout in the middle of her Pilot...there's some hope! I also agree with Jenny's suggestions of the Radian and Cargo, assuming they fit (Cargo should be fine, Radian works great with LATCH, but is iffy with seatbelts in the center).
Julie CPS Tech and mom to 3 in seats
http://www.cpsafety.com/articles/RFAlbum/SarahMA.aspx

[MamaKto3]

thanks so much for your opinions and replies..
so do you think a Marathon, RA, and parkway would fit? I just assumed that they wouldn't.