I had not. When it comes to buttons, I wanted quiet, easy to wire buttons that I can wire to the i-pac board.
The gold leaf buttons looked to be the best buttons to get, in terms of response, quietness, and look.
Are the Happ buttons you mentioned have the same look and sound as the gold leaf buttons? Nothing would bother me more then having 3 players with buttons with the same sound and look and have the fourth player be something different