Roy Oswalt isn't a free agent, yet, rather he has a team option of $16 million for 2012 or a $2 million buyout. With the Phillies other pending free agents needing to be signed (Rollins, Madson, etc), Hamels needing to be locked up long-term, and Howards $25mil/year extension taking effect in 2012, the Phillies aren't expected to pickup Oswalt's option.
2011 was kind of a weird year for the other Roy. He was uncharacteristally 9-10, suffered some back injury issues, and left the team for a few weeks after his home was destroyed by a tornado in Mississippi. He rehabbed the back injury, which coincidentally occured not long after his return from Mississippi, and his stuff returned to the low 90s range. At a generous 6'0", he has never really been an overpowering pitcher, but more of a finesse type with some good movement on his fastball.
Sorry for the lack of statistics, but I don't have time to go digging. I'm pretty sure that Oswalt has always had a decent GB/FB rate, and lower HR allowed totals, especially for the band box that is Citizens Bank Park, which should translate well to the K.
So what would it cost for us to sign Roy? would he sign in KC? He turned 34 at the end of August, so he must know that there won't be many more contracts for him to sign and he will undoubtedly be looking for a WS ring. Given these issues, I can't see KC being high on his list. If however the bigger clubs aren't offering him the contract he would like, and he is getting lost in the shuffle in free agency due to his age, recent injury history and status as a #4 SP in Philly, maybe we have a shot. I'm thinking he would consider 2 yrs/$25 million to come to a rising KC team and be an ace again, in order to get his value up for his last and probably final contract.