Decision made, going with air actuated turnouts on my new garden railroad. My dad has used them for 20 years on his indoor layout so I'm very familiar with them. Inside he uses the air toggles on the control panels but Outside I will be controlling the air to each switch with a solenoid valve as others have documented here. Just wanted to pass along this tip if you are going this route. Don't buy them from Sunset Valley or Clippard. New ones will run you $40 each plus the manifold. Used surplus solenoids can easily be found online for much less. Most will be 24V instead of 12V but that is a minor thing as I'll be controlling them with MOSFETs or relays. Search EVO-3M or EVO-3M-24 and you will find lots of options. I picked up these for $60 for 8 valves and the manifold. Try the ususal places, Ebay, Surplus City etc.