how different are the pistons im looking for new pistons and rings for my d15 block but i ofound a good deal on d16 pistons and rings

 

Which set of D16 pistons and I'm assuming the D15B2 Block, correct? There aren't any differences to my knowledge other then the design of the pistons, i.e. flat-top, dished, domed etc. But the key thing to know is where the pistons came from.