You're running reverse? Are you bashing or racing? I would disable it for racing - it will help prevent the 'accidental' reverse syndrome.
The 'front arm problem' refers to the front lower arms being very weak at the gearbox end - they have a tendancy to break away at that point (where the hingepin passes through them).
Having said that, I only broke one when I hit someone's foot at nearly full speed...
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