What’s not to like? I gave the auto focus only 4 out of 5 stars simply because it can be just a bit slow. Not critically slow, but a little quicker on the draw would be nice. Aside from that, the only other minor complaint I have is that the locking mechanism can be a bit tempormental and require a little persistance to get it to lock the zoom in place. I susspect that is sort of specific to my lens, as I’ve not heard anyone else mentioning this issue with their lenses.This would be an absolute dream lens if it apertured to 2.8, and if it did, I’d probably hardly ever remove it from my camera, but alas, you’re just going to have to work around a narrower aperture in those lower light situations if you want to purchase this glass.Aside from the items mentioned above, it’s a killer deal for what it costs. It’s superbly made, solid, and for the 150-600mm zoom, it’s pretty compact and very reasonably priced.For those of us that don’t have $20k to spend on a super-telephoto lens with a 2.8 aperture, you just can’t beat this alternative.Most definately would recommend this lens. It’s a steal.