Engine

Was just a general discission on STM, which was designed for the newer sensors that followed our 500-550d's such as the 650 + 60d. Don't think there is a major problem with the lenses just that you will not get the faster focus. But if you go to Park Cameras which I think you probably wil!! I'm sure they will help you a lot than me..

  Beer.

            Thanks for that Dave, most of my pics are landscape or architecture and if it wildlife when that would count I would be back on the 55-250 anyway so maybe it should not make such a difference anyway.