No exp with the truck tents, however I have gotten some lessons in tents in general in the last 3 years.
The cheap ones are OK, and if you treat them well it will last and be dry. The first things I would get are:
1. A silicone spray product, like Camp Dry
2. A good sized cheap tarp.
3. A cheap tarp that will fit UNDER the tent.
Treat the tent right after you get it, you can go with seam sealer also but the spray will probably be enough to take care of the rain, if not, you are right next to your SUV, throw the tarp over the whole thing and stake it down. Treat it twice and let it dry after each application. Aluminum spikes for gutters work well for extra tent pegs and they are cheap. The tarp that goes under should not stick out on the sides, because if it rains it will hold water under you. If the one you get is a little big, just fold it under.
I own a big cheap one, a 15+ year old Coleman Sundowner 3 man, that is still in good serviceable condition even after all the use with the scouts and before, and now 2 Eurekas. My personal preference is a hammock
http://www.campmor.com/outdoor/gear/Product___40677 when packing and a Cabelas fat guy special cot
http://www.cabelas.com/sleeping-bags-cots-accessories-cabelas-outfitter-xl-cot.shtml when car camping. That cot is the cats whiskers. Though a tad heavy for the ALICE pack, your back will thank you if you only have to move it into a tent. I use the rain fly off of the family tent for a tarp for the hammock and have set up the cot, zip tied the the short tent poles to the cot, and used the rain fly over top. Worked great.