Originally Posted by
GoSharks
I think you misunderstood the OP...
Anyways, at least with Rival brakes, they come with Swiss Stop pads. No need to replace those.
Nope, I think the OP doesn't know what question he's asking.
He has Apex, not Rival; and there's no saying that the calipers are even Apex at all since he says they're unmarked.
The only time I would recommend changing calipers is if the ones on the bike don't have a centering screw. Dirty cables affect feel, yes, but not stopping power (not unless they rust through and snap, anyway). Road bike tires are also so skinny that any differences are relatively slight.
Pads make the most difference. They do the most work. Swap out crappy unbranded pads for good ones (Kool Stop, or Swiss Stop, or even the current-gen Shimano DA and Ultegra pads) and braking performance will be as good as it can get on a road bike. I couldn't justify ditching the cheap Tektro calipers on my last bike after I put good pads in.