What I really like about the Tamron G2 verson is it's close focusing capability. I shoot a lot at the Patuxent Research Refuge - North Tract just outside Laurel, MD where I live. That land was used for live-fire Army training before it became a research refuge. There are some trails that are safe to walk on because they have been cleared of live munitions. For the most part you are restricted to standing on the roads. The close focusing ability allows me to shoot closeups of plants from my car on the road. By the way, I use the lens on my Nikon D700 and my D750. I also have the matched 1.4X converter.