Yes there is a definite advantage to Air Up/Spring Down. On an Air Up/Down system if you lose air pressure while flying and your gear is up...they aren't coming down. You can try to do some barrel rolls to get them down, but your guess is as good as anyones if they are locked, get ready for a belly landing. Worst case scenario, your out of air, do some barrel rolls and get one leg down, get ready to make some repairs depending on your flying skills. With a Spring down system, if you lose air pressure the gear automatically extends and locks.

The Robart 700's are 90 degree, Air Up/Spring down, rated for 8 to 18 lbs and accept 7/16 (larger and less likely to bend on a rough landing) and 3/8 Struts. Limited Quantity in stock at Tower 119.99.