I've tried about every deer feeder and slinger system out there. The Sun Slingers are pretty good. However, I've switched to almost exclusively using Spintech feeders mounted on 55gal barrels. Squirrels won't chew through like they do on the plastic barrels and the Spintechs keep varmints and cows from knocking corn out. I plan on adding my own solar panels, which can be had on eBay for about $10 each. Then I won't have to worry about recharging or replacing batteries.
Ghost blinds do work like a champ.
Ghost blinds do work like a champ.