Firstly the allow longer between the blips of the key for the functions seems to be the right thing to do. 2 distinct blips works best, not double blip 'mouse' pc style. I know this from the 3 required with Reinhold module fitted.
As for distance. I must have some sort of Star Trek 'warp' key. 3 blips from 50 feet or more away and the roofs fully retracts before I can walk to the car. It's my sports centre party piece much to the surprise of passers by that the car is ready as I get to it
My "twerp" key works only if I am within 10-15ft of the car and I have attempted this under a dozen scenarios, ie. city, suburban, rural. I wanted to see if other RF signals interfered with transmission strength. The rural worked at the longest distance: approx 15-20ft max, McDonald's parking lot I had to be next to the car before it worked at all. Go figure.