I have not dealt with him but I do have the Mr Alternator one on my 4Runner. It works ok but the engine has to be running at 1000 rpm or more for any output, mine idles at 850 rpm. It sucks to be at a light and have your lights dim because you have only 12.5 v battery power and then step on the throttle and watch your lights get bright again at 14 v.

I have been looking into the GM 10SI alternator, Powermaster #PWM-47294 140 amp from Summit Racing. I have an extra bracket and just need the time to modify it and it would put out 101 amps at idle. If your interested, here is a few sites that might help.

85 Toyota 4Runner Alternator Upgrade Project

GM CS130 Alternator install