I bought one of these 300mm 2.8 a couple of years ago. Excellent lens, a real step change from my 160 -500mm Sigma. The results have been quite amazing. The only drawback is portability. Its heavy to cart around on your shoulder/neck. I use a Kata photo rucsac which is excellent. The only problem is when you need the camera in a hurry, it takes a good minute to open bag, reverse the lens hood and get the kit shooting.
On the whole though, the 300mm 2.8 combined with a 1.7tc is an excellent birders lens.
Richard
On the whole though, the 300mm 2.8 combined with a 1.7tc is an excellent birders lens.
Richard