I bought an X-cal3 Tuner from Doug at Bamachips about a month ago. At first i was freaking out cuz i couldn't get it to work then after it was working i didn't it made much of a difference. Well let me tell you folk THIS THING IS AWESOME! I bought it primarily for use at the mud drags. Prior to tuning my truck i was running 5.1xxx sec times consistently (I was actually so consistent that i won first place in Mens Consistency) Last race my best time 4.57 sec. Thats more than a half a second gain and only 150 ft to gain it in. And no the mud conditions have little to do with it.
There was this Rubicon that ran neck to neck with me the last few races and ended up winning. It was like my fastest time was faster than his slowest time. This time i stomped him in in all four passes in both the street stock v8+v10 and in the super stock 4cyl + 6cyl and took first place in both classes.
My favorite part about this is the setting the trans shift points at WOT. It used to shift into 3rd and bog down... now it shifts into 3rd and i can get 4000rpms outta the engine.
Props to Doug @ Bamachips