if they're both using the kce-422i cable to connect, there shouldn't be. i used that cable with the 9887, and it worked great. there was BARELY a hesitation, as in if you weren't just critically paying attention, you wouldn't know it. it was leaps and bounds over alpine's older ipod interface, the 420i, which i used to have.
if you're looking at those decks, i'd also consider the 9886. it uses 24b DACs instead of the 1 bit DAC in the 9885. They'll probably be about the same price online, and the 9886 is newer, so you'll have more luck finding that one from your local shop.