While the center wire is on the thin side for my liking, the superb resolution and vibrant contrast atoned for this and allowed for the reticle to be seen easily through legal shooting light (30 min before sunrise and 30 min after sunset) . Mine was the 3-12x50, and at max power, the illuminated dot registered around 0.75" on my grid at 100 yards. With the illumination off, the dot is smaller and just over 0.5" at 12x/100 yards.
Here are some key specs:
http://optics-info.com/leica-eri-3-12x50-rifle-scope-reticle-subtensions/
