Uhh, I dunno what you are looking at, but that unit at the bottom of the Mesa Performance page is the EXACT same unit I posted as available at Performancedepot.com, for like $10 less. It does not have it's own button, but wires in to the existing harness.
I have pictures of the units installed in mine, if you like.
One-touch up, one-touch down, uses the existing lighted switches, or you can use the E36 ones, whatever.