RE: prop size for an os .61
I agree with "overkill" statement for Tiger 2.
For your references, here are the places where you can get this info in the future:
[link]http://webpages.charter.net/rcfu/HelpsHints/PropSz.html[/link]
[link]http://www.top-flite.com/accys/topq5000a.html[/link]
Hope this helps.
Good luck!