Hi rcfan450
I have used quite a few gyros on my Jets. They work great to calm down a jittery bird, or fix crazy nose wheel steering issues.
I just bought some HK401B's from
www.hobbyking.com, they have them on sale for about $14.00 now and they seem to work well, but I have not flown them yet. You will need 2 ch to run them the control channel and the adjustment channel. The nice thing is you can adjust the sensitivity from the Transmitter. From HH to off to stablization.
Using gyros has allowed me to even move the cg on my friends F-22 to an almost un-flyable aft cg for better performance.
If you are going to start using gyros please make sure you insulate them from vibration well and make sure before you take off that they are operating in the correct direction. Oh and HH gets real interesting in an airplane... have tried it a few times with weird results. There is a great article on Futabas Japan website in english
http://www.rc.futaba.co.jp/hobby_en/...al/tech01.html