I've always been very happy with my Nelson tune. The funniest complainers are the ones that say a speed density tune sacrifices driveability. I can show you multiple trucks including mine that work great hot or cold and any altitude. Also I know of one truck Allen tuned on the east coast that didn't run right. Retune after retune it still didn't run right. Allen asked him repeatedly to try another MAF sensor. The customer finally shipped the truck to Allen's shop. The first thing Allen tried was a MAF and guess what, it ran perfectly logging it with O2 wideband and all. Allen reloaded the first tune he sent and it also ran perfectly. After that Allen repaired all of the messed up install the customer did on the STS system and sent the truck back in perfect running condition. I'm sure there are pleanty of good tuners out there. Hell Allen will tell you the same. Just weigh the complaints with some doubt as to the condition of the customer's vehicle and their ability to mess things up!
2006 Superior Blue Trailblazer SS AWD, Stock as a rock
Sold: 2002 GMC Sportside Denali front end with a 2002 LS1, FLT level 5, Yank 2600, Trick Turbo, T76, Nelson intercooler, 60LB injectors, Warbro fuel pump, Eaton locker, Magnaflow, 3.42, Nelson Performance Tuning (speed density).
Sold: 1981 GMC LB RC 1500 2002 4.8L 4L60E 12 bolt 3.73 Richmond Lock Right AC PS Nelson Performance tuning