I'm in Calgary at 3500 ft riding into 5500 ft roads.
Have Yosh TRS slips ons.
Am using the map by the chap badged Lord Duck Hunter.
Excellent map based on dyno runs with Moriwaki slip ons.
A huge difference from the factory map, and way better than the map in the PC III or the Erion Brothers one I also tried.
Key though is what so many miss.
Be sure to synch your PC III to the throttle positioner - it's in the PC III USB manual about how to do it.
I just took my laptop into the garage and plugged it in to the bike.
You can also "proof" the accuracy of your tachometer too !
Back the the synching.
You want the "map" co-ordinates to perfectly match the throttle position.
If your setting is off a few points, it won't make much difference up in the revs and under a fair bit of throttle, BUT at low revs and small throttle openings the negative effect is going to show up.
You'd be amazed how many people put on a PC III USB, dump in some map, and are not even aware of the throttle position synch tool in the PC III USB.
By the way, you don't need an "altitude" map.
The Absolute pressure air box sensor can tell what altitude you are at, and makes adjustments to correct.