Ummm, I seriously doubt the stock wheel has an offset of 60mm. I'm more than postive it's 52mm. I looked around for wheels alot, and in doing so I researched all the stock offsets for a variety of wheels Mazda offers.
I know my Miata wheels have an offset of 55mm. But the 6 is definitely 52mm.
Regardless, 50mm offset on the Kosei's will be imperceptible when you put them on.
I ran around with RX-8 rims this past season and they have an offset of 50mm. I ran the stock tire size for the RX-8. Never truely appreciated light weight wheels until I went back to the stock OEM wheel for the 6 for this upcoming winter season.
The car behaves a whole lot better. I took a chance on the RX-8 rims because they're a very nice looking OEM rim.
But I would definitely stick with OEM dimensions for the foreseeable future. And definitely a lighter wheel.
I can't wait for the new spring season!

quote name='jd42' date='Oct 16 2009, 03:13 PM' post='1609362']
Actually, the OEM 17" wheels are +60mm offset. You are correct that the +50mm offset wheels should be fine with 215/50R17 tires.
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