Oh well it is only my opinion, but it is the primary reason I switched from Mugen. I broke quite a few front lower arms on my Mugen and also bent a few universal dog bones. The truck getting slower over time was expected based on what I have seen with the buggies for the last 5 years. I thought they had it fixed with the 5t/5r shocks, but I guess not.
Everyone around here has dumped their Mugen over the last few months. Most have switched to the Losi 2.0 and a few have switched to the OD.