I have since finished the build on my car. Trex, z06 heads, fast 90, nw 90, spooled 9" w/4.56 gears. Car runs really strong, pulls insanely hard, driveability is great MOST of the time. Every now and then, I get a shudder, stumble, hesitation, pause...usually when pulling away from a stop or a driveway. On occassion, the hesitation will happen while cruising. I'll give the car a tiny bit of throttle (as in enough to maintain speed going up a slight incline) or when in 6th for extended periods of time, the hesitation is very noticable. It almost feels like the car is loading up with fuel, and I have to "clear" it out. I was throwing some codes for both 02 sensors and the TPS. I have since replaced the 02's with #13111's and installed a new GM TPS. I still throw a code for the TPS and still have the stumble issue. Car has been tuned already, however I will be making a return trip to the tuner for a tweak here and there.
Could my issue be related to the tune? Or possibly something else?

Thanks for any input!!