Robin, the OE ATU isn't an inherently bad device, it just requires observation and maintenance. But it doesn't usually get much of that, and when it's been sufficiently abused it can go rogue and start eating pistons. Any electronic advance will dodge that bullet. I used Boyer ignitions for years, but I really don't like the design. The timing plate is mounted over the Hall effect magnetic rotor. This prevents visual inspection. If that isn't a bad enough design feature, the timing plate is flimsy and mounts on the edge of the ignition housing, which doesn't support it all the way around. The first Boyer system I installed lasted more than 15 years. The next one was in use for less than two seasons before it caused trouble. I put in yea, many hours of troubleshooting in search of the cause of a 6500 rpm breakup before pulling the timing plate and finding that it had warped concave to the point that the rotor was contacting the solder pads on the back of the plate. I bought a new timing plate and reinforced it with a bit of extra fibreglass. It worked. Later I installed a Probe ignition, and never looked back. (Sadly, Mark Whitebook has discontinued production of Probe motorcycle ignitions). I've never used a Pamco ignition, but the e-advance Pamco system looks to be better designed than Boyer.
