Question about pot odds..

[colos1]

This is a situation I've run into a couple of times and I was wondering what the right move is here. Lets say I am dealt J10 offsuit and the flop comes up Qs 9h 2s. I hvae 8 outs for the nut straight draw, no flush possibility for me, but there is the possibility of there being a flush chaser out there. Do I still calculate pot odds with 8 outs or do I figure out pot odds with 6 outs getting rid of the K & 8 of Spades becuase that will put a flush on board. Sometimes this can mean the difference betweeen calling or folding a hand. How do i play this one? Do I assume there is a flush chaser out there or do I aassume my hand is good if i make my straight