The Fuji Guys take the Fujinon XF 100-400mm f/4.5-5.6 R LM OIS WR, XF 55-200mmF3.5-4.8 R LM OIS and XC 50-230mm F4.5-6.7 birding on the Fujifilm X-T10. Out of the three I think the XF100-400mm is the best performer and I highly recommended it in my review, but the XF 55-200mm is the best value.