I am planning to do the same thing soon. I have been speaking to Jay. Can you tell a noticeable power difference? I know people speak about the pulsar and the throttle response, which is great but I am hoping the custom tune will do that and more.
The Custom Tune from Jay is better than Pulsar in the shifting through the gears, it is quicker and smoother. The rpms do not drop down nearly as much... they stay up and the responsiveness between each gear as the rpms go up is effortless. Keeping in mind that the truck is SO heavy it moves through the mph much quicker. Prior to the Pulsar it was late through shifting... and it seemed to bogged down. Once I got the Pulsar Edge,
it was an improvement but still not what you expect when passing i.e. a semi-truck or whatever. Now with the Jay Greene Tune... you can watch the RPMS stay up and the truck is quickly switching through the gears. I was lucky enough this morning ... in a safe environment, (semi-closed Road) to go from 0 - 96 mph. It felt effortless, and quicker. I did another pull at 38mph to 90mph.... I use to see a little lag on the dash as you look at the gauges and felt that lag in the seat of your pants - now that is gone.
For me, I am looking to do some more things as I coordinate with Jay to increase the power -
for my taste the truck is not where I want it yet so I am starting next stage.