I've had excellent service from the OS plug. They last forever and the only reason I fit a new one is because I can't remember the least time I changed it and think it must be about time.
I haven't used the other brands so can't comment there, but I see no reason to change if I don't have a problem.
As for the OS haters, most of them think that if there is a cheaper engine out there it is just as good and that OS are ripping them off.
They forget that OS put in all the R and D to get a good reliable engine and then it gets copied by companies who don't have to do the R and D.
Ultimately they end up with an inferior product. If it wasn't for companies like OS, there wouldn't be the cheap copies anyway as they would have nothing to copy.