[BMPOWERED]

My kids are now 4 and 7. I've had everything configuration from a rear facing seat in the middle with a convertible car seat on the outboard, to currently a high back booster on one outboard seat and a convertible car seat on the other outboard. With the original middle and outboard seat configuration, I was still able to SQUEEZE an adult in the other outboard seat. In the current configuration with the 7 year old's Graco high back booster, the fixed headrest does NOT create a problem. The only area of concern would be if you plan on having a second kid (meaning eventually 2 forward facing car seats), forget about fitting a 3rd human in the back seat. On a side note, I was also able to fit a full size Chicco travel system stroller in the trunk!