I don't have a strong opinion on whether a PC based system is good or not - although i would assume that a dedicated board set would be more efficient at running but more expensive to develop AND at least a dedicated boardset with largely through hole components can be repaired by the hobbyist.

I wouldn't be so sure that Stern is sticking with their boardset. Here is a photo i took earlier in the year of an ACDC premium with a boardset i had never seen before. It was a local guy that bought it for home, and then called me as it was shooting balls out on power up. I assumed it would be a trough switch, but had no idea where to start once i opened it up. There are a heap of under playfield boards linked by network cables - unsure how smart it is to have lots of soldered components near solenoids with lots of vibration.

Old mate ended up being given a replacement machine by AMD, so not sure if this was sent by mistake or not?