From an air-traffic standpoint- if you train out of RHV, you'll experience fewer problems with traffic and poor weather than the other airports such as San Carlos, Palo Alto, or San Jose. Just be sure you have GPS in whatever plane you learn to fly- the Cirrus SR22s are equipped nicely and have a parachute in case of emergency. Flying is really tricky around here- remember to not take chances with the weather- several General Aviation pilots have wrecked into the mountain ridge next to I680 because of poor weather
