Had an 05 Titan and loved it. Family needs required a vehicle change and I miss that truck! Mine wasn't an offroad model, but I was able to pick up a set of offroad wheels off craigslist and move to 33" BFGs. Handled very well and tons of power on tap. As with all Nissans, aftermarket parts (lifts, armor, etc) are more limited than with other trucks, but there are quality parts our there if you search around. Turning radius was a wider than I would've liked but most full size trucks are likely similar.
Power/fuel mileage. MPG in any full size 4x4 is not going to be good. I could drive it easy or more aggressively, run it empty or carry a load and the mileage never really varied that much. Tried to see if I rolled slowly away from stop lights and eased into the throttle if it would have a significant impact on MPG, but it didn't. Decided to just drive it and not worry about the MPG. Made it a lot more fun!
Good truck with plenty of power and good handling for a big truck. I say go for it!
Disclaimer - we've had 2 Pathfinders an Xterra and a Titan so we're Nissan biased.