Pinball Life 8-ball trough. 
This trough can be used as a 5-ball, 6-ball, or 7-ball trough by simply removing any unused switches.
High quality PCB opto boards are used for tracking the ball in position 1 and the jam/stacked ball position.
It really doesn't get any more straight ahead and easy to use than this!  Perfect for homebrew machines.
Need a ball trough that handles 4 or less pinballs?  Check out the link below.
Pinball Life #PBL-100-0016-00.