Chip Upgrades - 3.4 engine

I am looking at both the Powerchip and TAP for my engine...does anyone have experience with either? www.powerchipgroup.com and www.tap1.com

Powerchip offers 15hp and 9lbs on 91 octane, Tap offers 22hp and 24lbs but no word on octane at this point.

Either seems like a modest gain for the price but both claim to help take care of the flat spot around 3k rpm.

Thanks,
JMG