I wouldn't feed them medicated starter, let them build natural immunity so they aren't reliant on medication to keep them from getting sick, which I why I would also never use a wire bottom brooder. Thats just my opinion though, and I'm sure theres plenty of people who disagree. To me, the best coccidiostat, which is what most medicated feeds aim to do, is proper hygene for your chicks. Okay Im done with my soapbox now, sorry.
Feeding chickens is not rocket science. If you feed them starter/grower fora little longer or a little less time then reccomended, its not going to hurt. Because I keep so few chicks at one time, I often have the same bag of starter for longer then their reccomended 16 weeks and I just give it to them until it's gone. I know some people who do not even use a chick starter and opt for a higher protein feed such as game bird from the start.