Originally posted by Malsi Is there a big difference in terms of quality?
The difference is significant wide open, the DFA*70-200 is sharp from wide open (defective copies excluded) with some star* like image rendering (microcontrast+color) and the build quality is really nice, at the cost of weight and price. Although, no one should expect fast AF for sports, that's Pentax. DFA*70-200 and Tamron SP or Sigma don't really compare with regards to value/money; those OEM lenses are sold as premium lenses, it's the same with Canon, Nikon, Sony 70-200 f2.8.