An OEM board is always preferred to any aftermarket board.
Years of data and fault information have been accumulated for the OEM boards. We know how to repair them.
Some folks might cite "preventive maintenance" but I'm in the "if it ain't broke" camp. I have backup PCBs, but I'll never remove a perfectly working board to futz with it or replace it. A few exceptions: NVRAM or at least moving batteries off the board, Gottlieb System 80B/3 power supply and Classic BallyStern Power/Driver board voltage trim pots (these can fail in ways that allow much higher than design voltage onto power busses. And of course, if someone sends a board to me for repair, I'll bulletproof it to remove the possibility of future issues (cap C2 on a WPC Power/Driver board, for instance...it leaks). No sense in shipping a board more than once.
The very best aftermarket board would be a trace for trace copy of the OEM board, with minimum deviations to accommodate better design (such as replacing bridge rectifiers with gangs of diodes). Aftermarket boards should follow the part naming of the OEM board as close as possible. And of course, an aftermarket board should work...like the OEM board.
PinLED makes a nice board. My only comment on it is that a bunch of logic on the OEM Power/Driver board was replaced by a single CPLD with proprietary PinLED code. If that chip goes, it's back to PinLED for repair.
RottenDog...no comment. We're all up to speed on the issues there.
DumbAss Power/Driver board...made meticulously by a perfectionist with a stellar reputation. I have no hesitancy whatsoever using any DumbAss board in my games or in my client's games.
There are other aftermarket WPC boards out there, but I don't have enough experience with them to fairly comment.
I do like the design decision made by some to use surface mount chips (for ease and speed of manufacturing) with the PCB designed such that if the SM part fails, it can be removed, and replaced in a provided through-hole location. Alltek does this for some boards. Weebly does it for his 6803 MPU, Bally/Stern Lamp Driver and Solenoid Driver boards, and perhaps others. Someone made a WPC MPU with this design but I can't recall who that was.
Gottlieb System 80/A/B aftermarket MPUs are all difficult to work on as none of them mimic the OEM board.
My opinions only. YMMV, of course.
Chris Hibler - CARGPB #31
http://www.PinWiki.com - The Place to go for Pinball Repair Info