There are some Rottendog boards i like, and some i don't.
The WPC cpu board replacement by RD works well and i've seen them in some games for years without issues.
The DMD controllers for DE also are good from RD.
RD power supplies for system1 and system80 work very well and have a nice price point.
RD system11/DE power supplies i don't like so much. but they do work. but the originals are easy to fix, don't know why people replace them.
the DE cpu board from RD is nice, works well.
the williams sys11 cpu board from RD i am very wary. same with sys3-7 cpu combo board. much prefer originals. RD version works in a pinch though.
the sys80 cpu board by RD i don't like at all. had problems with it.
The RD wpc driver board i don't like, and it doesn't work well in IJ/Popeye/STNG/Demo/TZ. but i never understood why anyone would replace that original board as it's the easiest thing to fix in pinball!
As for replacement LED score displays, love the RD ones. All of them! They are awesome and have a nice price.
As for xpin/pinLED boards (all/any of them), i would NEVER EVER use their boards. Oh my gawd, talk about unrepairable over engineering that often doesn't even work out of the box. i've been burned by them too many times.
in conclusion, original boards are the way to go. but in a pinch, RD in most situations works well and has a decent price point.