I've never used the 70-300vr, but for many years I used the older Nikon 75-300 and later the 80-200 f2.8 with diopters and they are both capable of very good close-ups. One two-element diopter you might want to snatch up if you can find it is the Pentax T132. The neat thing about that one is that it is only .76 diopters. So if you do the math that gives you a focusing distance of 1.3 meters from the front of the lens when the lens is focused at infinity. Thats right about where the 70-300 is at with MFD when used alone. It's a great diopter to fill the gap between the lens with no diopter and the lens with something like a Canon 500D, which is the most readily available two element diopter today. On the 80-200 f2.8 the Pentax diopter provides even better image quality than the Nikon 5t and 6t and better quality than the lens alone at minimum focusing distance and 200mm (a known weak spot for the 80-200). Another great thing if you are using the 70-300vr is that the T132 is 67mm.