RE: The 47" Arfs
Just get the 65" Yak arf. They are way better than the F90. The saito 180 will be fine. Just a tad overpowered. Plus if you are just learning, what a great plane to fix up anyways. ITS A PROFILE. They are tuff and way easy to fix.
Yes I have a YS120fz in mine. It flies fine. Just a tad nose heavy and will have to add a couple oz. of lead to the end. Oh well. I've got tons of power..... It floats in great.