nex-7 uses aps-c sensor, which should be on-par with nikon aps-c sensors since sony makes sensors for nikon. image quality should be very good
however for the price i think you are better off with either a canon 7d or nikon d7000, both of which will provide better build quality, access to more accessories etc.
however for the price i think you are better off with either a canon 7d or nikon d7000, both of which will provide better build quality, access to more accessories etc.