Len. i would imagine that it costs no more to build a 2.4 set than it costs to build a 27mHz set, at source nowadays.
Phil. Subs, now I have built one (and its SO EASY) and it goes down (and up) on command….well.. theres nothing better…after all…what do model boats do?? go around and around… yawn….

impresses small boys no end. of course if yours keep on breaking down, well….
Ashley. (known for blowing own trumpet….or Sax really )