I've put it off as long for as long as I could but DS1 needs to move into a high back booster. I know the 2 way elite goes up to 25kg FF with the 5-point harness but I'm just not impressed with the side impact protection. We're looking at the Britax Kidfix and the Maxi Cosi Ferofix (any opinions/preferences on these appreciated!). So what do you think? Extended harness or good side impact protection? 