Practice and knowing your load ballistics gives you what Taperpin was talking about. Give a listen to Ron Spomer's podcast and you'll understand. MPBR (maximum point blank range) can take a target faster than dialing up to ~300 without hold overs because of typical bullet trajectory. Knowing...
I've always had the mindset that you don't need 2 things that are so similar. If you kept the 10x Leupy's and bought the Swarovski 15x I personally don't think the magnification gain will be enough to justify the cost, and they are so close in magnification it seems like they will occupy almost...
Basically it boils down to price, the more you pay the less traffic you have to deal with. Anything along the I-90 corridor is going to cost a little bit more but I'm my experience the traffic is much better than living anywhere on the I-5 or I-405. If you're not afraid of a long and fast drive...