I have a new Ruger Mini 14 Ranch Rifle, that I am about to buy a new Leupold scope for. I'm set on a Leupold VX-II, but want to get thoughts on 3-9x or 4-12x. I plan on using it for coyotes and small animals, maybe deer sometime. The 4-12x is about $40 more, but in not sure I need the extra power. Also, any thing I should do to get the most out of the rifle for accuracy?