I have tried a gyro and personally don't like it. IMHO it actually makes hovering harder as it introduces effects that are not expected and that makes corrections for movement difficult. The best advice I was given when learning to do 3D was get a good simulator (I use realflight) and practice, practice, practice. I watched a video by Mark Leesburg (I think) where he says he has over 2000 hrs of simulator time practicing rolling harriers. Folks that's a bunch of practice. After I could comfortably hover on the sim, I moved to a good foamy as suggested by the best 3D'er at my club and proceeded to practice on it. It was also suggested that I practice down low (tail no more than 2 to 6 feet off the deck) as it makes seeing the very small movements of the plane much faster and easier thereby making corrections quicker and easier. You can catch and correct an unwanted motion before it gets to be too much to deal with. It took a while but now I do it without even putting conscious thought into it. For lack of a better description, it has become "muscle memory".

Also, consider that the more tail heavy the plane, the easier it will be to hover. Too far aft though and it can become a handful to fly straight and level. Not a huge problem after to get the hang of harrier flight as you can just harrier land it. Burn lot's of fuel/gas and you'll get there. I honestly never thought I would be able to hover a plane 5 years ago and now it is almost too easy.

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