I installed the Soler TB 2 weeks ago. My android "Drag Racer" program shows a minor decrease in 60ft and 1/8 mile times, but could be atmospherics.
What I really am impressed with is the drivability in the 0-50% throttle area. I had a occasional hesitation when doing a rolling stop, just for a split second. That is gone. It's playing well with the Trifecta tune, 4.10's and 33" tires. I also have CAI intake and Magnaflow Overland cat back. Fuel mileage is unchanged, my mpg is solely dependent on my right foot. I can get 12-17mpg in town depending on how I drive.
Only you can decide if the improved drivability is worth the $275.