I thought the B4.1 RTR was very "meh" myself, and fairly fragile for a beginner, if the Losi 22 had been available, i'd have definitely gone for that instead.
And how much do the parts for an MM conversion cost? £20 ish?
(And plenty of guys at our club have run rear (and mid) motored 22s with no issues. All of them faster than me
)