Roofing: cost to replace roof OSB per sheet?

[Jack B.]

How much does it cost you your area to replace each sheet of OSB plywood by a roofing contractor in your area? I have a roofing company with solid 5 star reviews on every web site that everyone claims to be the best price and value in town who is asking for $55 a sheet replaced. OSB is $12.50 at Lowes, and I was a roofer 20+ years ago as a kid and know it takes a nail gun and about 60 seconds to install a sheet of OSB because I've done it. Am I being overcharged?