I'm trying to clear up a groaning/whirring from the serpentine belt area (it's not the PS pump) so I'm gonna replace the idler and tensioner pulleys (they had some drag on them).

Are the Dorman pulleys pretty legit?

I'm not going anything high speed under the hood so zzp, etc isn't my first choice.

Or maybe it's that crap Bosch water pump I installed.

I saw it has pretty terrible reviews ex post facto.