Shutter lag and AF performance is the typical of film SLR cameras as the old EOS 5 (my former camera) and the Rebel2000 (the film camera the dRebel is roughly based), and it's light years from ths typical digicam performances, so I doubt you'll have any regrets in this area. Very lowlight or nolight situations can be resolved using the internal flash as an assist light, with an efficiency similar to the infrared assist light present in the EOS 5, but it's more disturbing.