Help with Carseat/Booster??

I have a 4 year old and a 22 month old. They both have the Britax Roundabout, but my oldest is about grown out of it. I love the Britax and also would like to stick to a 5 point harness, but have no objection to boosters either. I was looking at the Britax Regent, does any one have this carseat and what do you think about it? What are some other ones that you recommend? I would like something that I can get for my youngest now too.

I have the Britax Husky, but they don't make it anymore. The Regent seems really nice-I'd go with it. I've tried Graco, Cosco, Safety 1st, and Evenflo seats. The Britax is far superior. All of their straps twist easily and don't seem as thick and secure as a Britax seat. However, at age 4 your son doesn't require a 5 pt harness. If he's over 48 lbs, he's too big for the latch attachment for your car and you need to use the seatbelt to secure the seat in your car. I'm all for a 5 pt harness, but a booster's fine. I'd get a high back booster, as opposed to the backless booster. As long as he's 4 yrs old and 40 lbs, he's fine to use the booster seat. If he's slightly less than that, he'll be fine. The boosters can be used at 3 years and 38 inches tall.