Thats what I was thinking stang but I welcome any advise as to what problems I may/may not have with each choice.

I thought a 52 fswould besimilar in power to a 46 two stroke and a 61 fs would then be even better but now I believe this is not the case and I dont want a guttless model (i know the spacewalker is not designed to be a fast plane) as she is quite a big bird that looks like it will have a lot of drag.