Question Extend2Fit vs Radian space front to back

I realized a couple days ago that my 2.75 year old's carseat expired months ago. Thankfully, I have a backup seat, so that's changed out. Backup seat is a Radian R100 that expires in 2020.

I'm thinking about getting another seat to replace the expired one, as I like having a backup seat, plus I hate rethreading harness straps (ahem... Radian). I'm looking at the Graco Extend2Fit seat. My daughter is around 37-38" tall (haven't measured lately, but she was 36" 9 months ago) and around 34-35 lbs. She tends to be around 95% for height and weight. She's a big girl. I'd like to keep her rearfacing a bit longer, and the Extend2Fit would do that very easily!

My question is about the space taken up by the rearfacing seat front to back. Which one takes up more space, the Extend2Fit (with extension pushed in all the way) or the Radian? The reason why I ask is because my husband rides in the seat in front of hers, and he's very tall. Right now, with his seat pulled up enough to fit a rearfacing carseat, his knees go into the dash if I have to stop quickly. He doesn't like that. So he's looking forward to her turning around. I'd like to keep her rearfacing for now. I thought I read somewhere that the Extend2Fit doesn't take up a lot of room front to back when the extension is not used. So does anyone know how it compares to the Radian? I have the back seat pushed all the way back (2008 Honda Odyssey) and the passenger seat is pushed up just enough to allow the carseat installation without bracing.

Thanks!

We have my son's Extend2fit on the passenger side of my parent's 2006 Honda Accord and I believe the seat in front of it is all the way back. My 6'2" 300 lb father can easily sit in front of it. It's amazing how little space it takes up for older children.

Yes, the Extend2Fit is very compact. My sister had issues with it in her Civic just because if she installed it as compact as possible, her kid couldn't get into it because of the shape of the door. So she had it in a less compact configuration. We swapped it out for a Radian. Her driver's seat is in the exact same position (a click or 2 further forward than she would like) but at least loading and unloading is easy now.

She moved the Extend2Fit to her Town & Country and loves it there.