I have this lens for several years and must say it can still keep up very relaxed with my newer lenses that are specially tailored to digital photography. It has a super-fast and extremely accurate autofocusing system (ultrasonic) motor which is beyond reproach. Even on my EOS 400D operates the Canon EF 75-300 4-5.6 III USM absolutely perfect and makes great pictures! I highly recommend this part only highly - not least because of Canon typically very good processing.