Overall, I like it. It definitely has move OOMPH than the mechanically stock 5.3 that was in it last summer. It's certainly quicker off the line, especially the odd time I had it in 4WD Hi, and tried a hard-launch. I really try to NOT beat on my DD, but I had to try it once. On the highway, I notice much less downshifting to 5th gear on long hills that would normally require it with the 5.3, but I doubt I gained much fuel economy, especially with the 33" tires. I did notice a slight bump in MPGs when running my winter 31" tires.
I do feel like the email tune has kind of reached it limit to fine-tune the cam and throttle, and basically all other stuff. It's been very helpful to just datalog, and do the email stuff, but I believe there's a level of polish that isn't possible with it. I have been desperately searching for a "local" dyno-tuner who can do LS stuff in person, but the search is not going well.
The other issue is the occasional warm-start/no start scenario. Again, I believe it's a tuning thing that has been mentioned in previous file revisions, but still not worked out.
Mechanically, the engine has been reliable, doesn't leak a drop (yay!), and sounds good. I'm trying to be financially responsible with a long-tube header plan, but adding cats. to the Speed Engineering headers (at least in my BrainCAD v1) seems to be holding me back. If I had a time machine, I would have just burned up a credit card a bit more, and bought them to install when the engine was out, but I was under an extreme time-crunch to get my daily-driver on the road.