The bigger the magnification, the harder to focus on an object whether moving or not, but if you have a very steady hand, you could consider the 12×30. Steiner claims that the 12×30 Wildlife Pro is easy to hold steady, even with 12x power due to the comfortable and ergonomic grip, but in the end this will be decided by the individual user. Fortunately the impact of less light due to the higher magnification has been countered by the wider objective lenses (30 mm).
The 12×30 Wildlife Pro differs from the other two in a number of ways:
1. Dimensions are bigger: 5.9Lx1.85Hx4.2W, as compared to 5.2Lx1.8Hx4.4W of the other two.
2. Weight: 13 oz. , vs 11oz. and 9.7 oz. Remarkably the 12×30 Wildlife Pro will also fit into a coat pocket. It is a bit on the long side, but definitely not too wide or high and still lightweight enough.
3. Close focus: 11.5 feet, vs 8.5 feet and 6.5 feet
4. Magnification and aperture (objective lenses size) are bigger.
5. Field of view narrower (220 feet, as compared to 264 and 333), making following moving objects more difficult, on top of the problem of dealing with the higher magnification.
6. Price: About 5% more expensive than the 10.5×28 and 15% more expensive than the 8.5×26.
Dimensions: (inches) 5.9Lx1.85Hx4.2W; Weight: 13 ozs.
Field of view: 220 feet @ 1,000 yards; Eye relief: 13 mm
Close focus: 11.5 feet
IP (Inter Pupil) Distance Range: 57-73mm