I would go for the evenflo maestro, graco nautilus, britax frontier or recaro prosport depending on your price point. They all harness to high enough both height and weights to get kids safely to a belt positioning booster age and make reasonable boosters for most kids (there's never a guarantee it'll be a good fit for your kid, but these ones fit most kids well). The maestro is cheaper at the outset, but you'll have to buy a dedicated booster later because it's outgrown as a booster around the same time it's outgrown as a harnessed seat.
We got the Britax Parkway SGL. I love it. It has a latch system so the base stays put in case there is an accident. It has a strap that comes up between the childs legs to prevent them from sliding under the lap belt during impact. It has great side impact protection. Some non-safety things I like... good padding and my daughter says it's comfortable. Has cup holders. It also converts to a backless booster if /when needed.
Sam's Club they had really pretty Disney Princess and Cars ones for cheap but good quality. We are using the 5 pt until he maxes out on size or weight b/c of safety benefits but we got one for my DH's car on the VERY rare occasion he picks Harm up from school.
Mom to Harmon 1/17/08 and twins Rachel & Callum 8/28/09
Re: Recommend your booster seat please...