It's time to move my 10 month old into my 4 year old's convertible carseat, so looking for the next seat for my toddler. I'm looking for a seat that still has the 5 point harness but then can convert into a booster. The Britax Frontier has been highly recommended, but it's so expensive and we need two seats, one for each car. Does anyone have something similar to this seat but doesn't cost $300?? Thanks!