I have not heard a single one of my mom friends complain about their car seats. So my advice is to choose the one that fits best into your budget, as all are safe enough to meet the US standards. I chose the Graco SafeSeat because it goes up to 30 lbs., meaning that I could go from infant seat to car seat without a transitional one in between. I have a CR-V and this fits perfectly. Our hospital had a program that helped me install it the first time.
I used a snap frame rather than a travel system and loved it. They're lightweight, collapse down to almost nothing for storage and travel, and are cheap. I pushed that thing at least 4 miles a day for 6 months straight, and it's still trekking. I liked the Graco so much that I ended up buying their Nautilus 3-in-1 as my carseat , as well.
All my friends with the travel systems complained about the extra weight of the big stroller. Now that our kids are older they've all ditched their heavy ones for umbrella strollers for shopping trips/travel and joggers for heavier duty walks. So those bulky strollers they bought in the beginning just gather dust in their garages.
One poster mentioned getting a Britax because you can use it as an infant seat, as well. I would not recommend that. It may save you money (because you only buy one seat), but the convenience of an infant seat is worth a million bucks those first 6-8 months when babies sleep endlessly. You can transport them from house to car to store without interrupting their nap, which means freedom for you. We also took our baby on a few flights during the infant phase. The infant seat came right with us on the plane and into the rental car. The Britax is way too heavy and bulky for that.