A few months ago I picked up a used 07 with 72k on it. In the pics it showed the Pro 4x stickers although the owner did not advertise it as such. We had a good chuckle when I asked him about it and he admitted he just liked the stickers and picked them up off ebay
Point is 2008+ have the pro 4x package available but from what I saw it actually provides I wouldn't make it a priority. I am not in the position to buy new vehicles so i spend a lot of time i the old research dept. As far as I can tell the pro 4x has bilsteins and bigger stock tires with some basic underbody protection. The only thing you cant add yourself is the electronic locking rear diff,
as far as i can tell. I may be missing something else.
I have used it with bars and a RTT, and then I put a cheap used cap on it, plus built a platform with underbed storage. I much prefer the bed cap to the RTT. Not sure if your looking for backwoods camping or just a driver but in the PNW it rains. A lot. The RTT was good but anything below in the bed would get wet. We have talked about getting top racks for the RTT but I'm to old to be climbing up and unzipping that nonsense. Still have the tent in the garage but we may get rid of it. But I digress...
The only "performance" improvement was adding Falken Wildpeaks (not as good as the BFG's but a great buy for the price) and have had the beast on goat paths in the cascades and the coast range. I had zero issues slogging through PNW brand mud. I plan on adding Bilstein 5100's and better brake pads next. Some aftermarket parts are a bit more limited in comparison to Toyota's but there is plenty to get the job done. Bash plates are on the agenda as well but further down the road. There are some quirks, like every vehicle. Gas mileage aside, I chose the Titan over our other SUV every time. Runs like a champ, has plenty of power and easy upgrades like the air intake can provide some additional horses if you feel the need
Finally, the back seat. The only issue I have with it is they do not recline enough. It's just stupid because the rear seat has enough legroom for your standard sized NBA player. My 12 yo daughter loves it though, it's like riding in another county from the people up front.
Even with my 10 year old truck I hate to scratch the paint but if you live where there are tight trails you will get them, its wide. As mentioned MPG is written wrong its GPM in this beast. I usually clock about 12 mpg.
Couldn't find a good shot with the cap on but this is from a mixed moto/truck trip into the mountains in NE Oregon (plus my Yammie looks dead sexy);
and with the RTT in Idaho or Wyoming...
Needless to say, I'm a fan.