My position, I've done a fair number of iOS apps and am well versed in Ruby. The meta-programming aspect of RubyMotion is what appealed to me. There's a ton of boilerplate in iOS that could be eliminated. I attempted to migrate an iOS app to RubyMotion. I stopped because the debug tools weren't mature enough. It was a lot of fun to work with when everything worked! Like everything in life I suppose...

I will go back to RubyMotion once it has better debug facilities. And I won't do an app re-write; I'll do a new app. HTH. :D