Free: Contests & Raffles.
I have 15x Swarovski SLC's, I love them, I use them mostly in my truck because they are heavy, a lighter pair of 10x binos is better in the field. If you have a steady hand or rest against something you see through the 15x just fine. You can put them on a tripod and use a doubler if you don't have a spotter. But if you are planning on hiking a lot with them I would get 10x binos fo pack on your neck and a spotter to put in your pack. I used to have a swarovski spotter but sold it because of it's weight, I got tired of toting it around. I love my Leupold 12x40 Gold Ring Spotter, it's hard to beat the compact and lightweight build of this spotter.
For most country, I'd pick the 15's without a second thought. I haul mine all over, and the spotter rarely leaves the truck. You WILL see more deer using 15's on a tripod than with a spotter or any sort of binos without a tripod. I tried to deny this fact for many years and get by with 10's and a spotter, but eventually had to admit the truth that my buddies with the 15's were seeing more deer than me. Now they don't.