Hey Doug,
I'm almost in the same boat. My kids are 5 and 8. At this point I am using only the booster seats. One has only the bottom portion w/ armrests and the other just looks like an uninstalled racing seat. Both are used to go between the person and the vehicle seat and are only secured when the vehicle seatbelt is fastened, the carseats themselves have no belts. I like the full childseat best (full bottom, back, and headrest) and feel it is very safe for both my children, especially with the seatbelt locking mechanism. You know, pull the seatbelt out all the way and it will not let any slack out until it fully returns, then I'm the one determining how tight the belts are, not the kids.
I remember struggling w/the seats that had their own belts, had to be secured to the vehicle 1st, then use the belts from the childseats to secure the kids. When they were smaller I know it was necessary but man, all that linkage drove me nuts!!!!! I had the same issues. Always struggling to get it perfect. The clip helped but was a lot of work.
If your kids are getting big enough maybe it's not too early to start asking around to see if someone you know has something that will work better for you. It seems newer carseats are in abundance as they only get used a little while and friends/family are usually more than happy to get rid of them once they are outgrown.
I am very confident with my children's safety as now they are belted in nice and tight. If you want pics of what I'm using I can post them in a day or two, just lemme know. I have the same vehicle.
As far as the airbag sensor, I'd say it should be a bit more sensitive. Having had to stuff 4 kids in my truck, my nephew sits passenger front with the seat all the way back. He goes 100 lbs and he puts the light out no problem. I'd get that checked out. Maybe they can adjust the sensitivity.
Just a sidenote. When the kids exit I always belt the seats back in so they don't fly all over the cab. Gee it's to the point where the kids sometimes do it for me automatically. (miracles never cease)
One or two times they gave me a hard time about buckling up so I let them free while going up the driveway. Just a few minor maneuvers was all it took to convince them that Daddy had the right idea.
I also have the link to the Titan test crash dummy video, you can play it in slo-mo. It's on MSN (auto section) I keep forgetting, but will eventually get around to showing it to them. I don't think it's too violent considering what they see with playstation, and it should help them understand why we use seatbelts.
GoodLuck W/ the Childseat Blues
Chief