The 300 f4 will be an amazing lens and with the 1.4 converter all a wildlife photographer could dream about. I am already going to try the 40-150 2.8 on a safari and it works wonderfully with the same converter.
Apart from that, the 75 1.8 is an outstanding lens that I wish you all will have an opportunity to try!
Kind regards, Vieux Loup
The funny ting si that actual users of these lenses are very pleased with them.
As to faster lenses: i would heartily recommend the Metabones speed adapters, used with, e.g., Canon L-primes on MFT-bodies.
Kind regards, Wim
<a class="bbc_url" href="http://forum.photozone.de/index.php?/user/5408-wim/">Gear: 5D Mk II, a gaggle of primes, a lone zoom, an accessory plague, and an Olympus OM-D 1 Mk II, Pen F and Panasonic GM5 with 13 primes, 8 zooms, and 3 Metabones EF-MFT adapters ....</a>