I built 2 Arrows from MAN plans in 1980 (wood fuselages, foam wings/stabs). They flew great with OS .61VF. I also built an MK Arrow .40 with an OS .40VF - yep, it was a bullet - flew great - love those looooong slow rolls!!
I'll build another one (.60 size) but with fixed gear and all monokote!
Happy flying,
Will