Should be fine on your car, assuming you mean the rears. I have 17x9 in front with 275's, 17x10.5 in back with 315's. My quads are still there too. I'm also at stock ride-height, if you're lowered just do a reality check for clearance. 10's would probably be pushing the envelope for the front, both in terms of clearance and looks, so you will be doing a stagger.
Just make sure the wheels are designed for Mustangs. Or peruse the specs of known Mustang wheels (AM is a good site for this) so you can compare the offset/backspacing to the wheels you have in mind.
Some people think 10.5 is a bit wide for New Edges and are better for a shorter axle width like the SN-95, but I love the way mine look in the wheel wells. In fact since 275's do stick out a tad in front, if I didn't have 10.5/315 in the back I think it would look off. Note also that how you have your camber and toe-in set seems to slightly affect the appearance of how the fronts fit in the well.