After a hiatus of a few years, I'm getting back into photography as a serious hobby. I just bought a refurbished D500 from Adorama and I'm in the process of selling my old D7000 on Craigslist. I love wildlife photography, with a particular focus on birds. I used to have a Tamron 70-300mm f/4-5.6 VC, but 95% of the time I was at 300mm and it was often not enough reach, even with the DX crop factor in consideration. I'm looking to add a sharp, capable lens to my kit for around $1,000 and have come up with three options that meet my needs and budget, but I'm just having some trouble deciding what would be the best. As a hobby shooter, image quality is of course important to me, but it's not like my life depends on it. I'm not producing 60" x 40" gallery prints or working halfway around the world for National Geographic. The biggest print size I would make is probably 20" x 24" or 16" x 20", which any of these lenses can easily handle. Here's my options, from high to low price. I have no problem with used lenses as long as they're not beat up. ~$1200 - Used Nikon 200-500mm f/5.6 (300-750mm on DX) ~$1100 - Used Nikon 300mm f/4D and 1.4 teleconverter (450mm f/4 up to 630mm f/5.6 on DX) $800 -New Tamron 100-400mm f/4.5-6.3 Di VC (150-600mm on DX) Weight is a factor in this decision, so here's those numbers, from highest to lowest: 81.2oz - Nikon 200-500mm 50.8oz - Nikon 300mm (57.5oz including the teleconverter) 39.3oz - Tamron 100-400mm Although a 750mm f/5.6 would be pretty awesome, the weight, bulk and price of the 200-500mm Nikon puts it last on my list. Plus, I would definitely have to use either a tripod or a monopod for that lens, adding even more weight to carry around. Lugging that behemoth on vacations would not be much fun. The 300mm f/4D doesn't have VR, but I know that won't help me for moving subjects anyway, so I'm not all that concerned about it. The option to leave off the TC and have a 450mm f/4 at my disposal is also a nice bonus. The Tamron is the lightest lens and has VC, but it's got the shortest reach of the three I'm considering and also has the slowest aperture at it's maximum focal length. However, it is the cheapest option and comes with a 6-year U.S. warranty from Tamron. I'm not interested in any of the Sigma offerings like the 50-500mm F4.5-6.3 OS (too wide of a focal range) or 150-600mm F5-6.3 DG OS (also too wide of a focal range), so please leave those out of your suggestions. Again, I never used the shorter end of my previous Tamron 70-300mm, so there's no point in paying for a feature I won't use. Thanks in advance for all thoughts and opinions!