My in-laws have decided to buy a car seat for their vehicle and went out and bought an Evenflo Summit which I have told them they will need to return. I may be overreacting but the low harness weight of 40lbs is a big deal to me, specifically because at 2 1/2 my son is over 35lbs and 40" tall already. So now I am looking for suggestions for a long term seat for their vehicle (2010 Lexus RX). We currently have 2 Britax Marathons that we love but we are wondering if something with a higher harness weight and taller shell would be better for them. I just went to buy the Regent only to find out they are discontinues now so I am at a loss. Suggestions?? Thanks so much in advance!