If I went with a DI for bashing, I would carefully examine how having a much lower ground clearance would affect your bashing.
Also, if you get the DI, look into a rear hingepin brace as the tranny case is what holds the rear arms on. You hit wrong, you snap the case.
If I was you, make sure whatever 4wd buggy you have will also allow you to run truck rims on it. You can then get your RS4MT truck feel with a better vehicle.
One to look into would be the Academy SB V2. It uses a 12mm hex if I recall correctly, mount up some traxxas / rpm rear offset rims and tires (truck) and you are in business. You can even mount up a truck body too.
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