I dig that thule xporter setup. its pretty pricey, but as stated-half or less of a shell. But half the function as well...its nice to sleep inside a camper shell, not worry about your shit being stolen...at least not nearly as easy, and not having to scramble for a tarp to strap over the stuff in your bed when car camping at the river with the famly and it rains....or driving to pagosa in a storm... (dealt with all that and then some the first two years with my truck.)
A custom steel rack is by far the shiz with or without a shell underneath. those aluminum ones can be shady if you load em down, (at least the ones I have seen.)
If you look at campershells, Snugtop is the top of the line. Leer is the other best choice, but slightly more expensive IIRC.
I went with a Snug top high-liner model with yakima racks.(and all the other goodies like side windoors. since I was already going all in.) weight capacity for the shell is @ 300-some lbs. more then the yack rack itself. (@180 lbs supposedly)
Snugtop - Truck Cap & Tonneau Top Covers, Camper Shells Tops, Customized Truck Toppers, Pick Up Truck Canopy
They make a commercial topper which is thicker, more insulated and 400 lb+ weight capacity, but it is way more $$$.
Snugtop has lifetime warranty, and better features IMO. you can lock yourself in to sleep, and theres a button on the inside of the latch to let yourself out in the morning. and a light, windoors, 12 volt outlet, racks, etc...
I have been super happy with mine, after on summer with it. It's even been wheeling a bit and is still plenty secure. my old brahma was super shaky and rattly after 10 years and too many washboard dirt roads. it was literally falling apart.
o yeah....btw, check out tacomaworld .com..... tons of cheap/free mods, great classifieds, and a whole lot of other timewasting shite for tacoheads.
i have learned ALL kinds of stuff from there.