Who should i start as my flex option? Eddie Royal or Mark Clayton?

So who should I start between those two? Eddie Royal is going against the Colts. Denver has a good O line and the Colts don't have a secondary at all so royal could be up for a good day but he isn't ortons fav WR. while Mark Clayton is going against the redskins and they love to blitz which means he should be open but then again the redskins play 3 out in the back field with 2 safeties and a CB back and a CB close and clayton is brad's fav WR. I'm just so confuse. what do you guys think???