Replace brake pistons or not?

[JDM_Whore]

I was wondering if it's necessary to replace my brake pistons. The inside surface is completely covered in rust. The outside (inside caliper) is practicly rustfree, except on 2-3 places where there's a small amount right beneath the rubber sealing.

Can these be used again after removing all the rust? I've put them in a rust-dissolving substance untill tomorrow..

 

[Dannyboy205]

Hmm any pitting om the side of the piston generally means they should be replaced. In your case it seems its only as far as where the dust boot sits. If your budget allows it id replace them, but i think you could get away with using them. Sorry i cant give you a defo yes or no

 

[Jake123]

Clean them off, then sand them and polish up.
Should be fine

 

[Ellis]

if they arent sticking on and push back easily enough then as above just clean them off. if it isnt broke dont fix it