I have a 40-150 (non-pro) lens, but occasionally would like something with more reach. Casual photography, all outdoors, no birds, but maybe some surfing every now and then or just want the ability to zoom a bit more than the 150mm. Would like to spend ~$350 or less, and I know there are a few options. Regardless of the choice, I'd want to retain the ability to print large if needed (16x20 or larger). 1. Pick up a used Panny 100-300 or Oly 75-300 in the ~$350 range 2. Use the 40-150 with a teleconverter like the Oly C-210 (~30-50 on ebay) 3. Use the 40-150 with the E-M1's digital teleconverter 4. Another option? Would there be a big size difference between options 1 and 2? I'm unfamiliar with these lenses and teleconverters. Would #3 limit my print sizes considerably? Recommendations and/or pros/cons of each would be appreciated. I don't mine spending the money on #1, but not if it will only be a marginal improvement on #2 for substantially more money, especially since it won't get a lot of use. Thanks in advance.