Next car seat! Need help!! Diono vs britax

Nicki
My 5 month old has almost outgrown his infant car seat. We have a cybex Aton q. He loves it but his head is very close to the 1 inch mark of outgrowing it. I'm so torn between britax advocate and the duo I radian. I have a Yukon SUV so size doesn't matter. Does anybody have experience or suggestions?