I've borrowed a 30d in the past and now have a nex-c3. The nex has has a marginal edge in image quality from a high ISO noise point of view but its fairly negligible IMO. The Canon is a lot faster in operation and is built like a tank. The nex is a lot smaller and lighter. The af is way faster on the Canon, but more accurate on the nex for still subjects. The Canon wins hands down for tracking moving subjects. You might feel you'd lost as much as yous gained, unless video is that important to you.