i used to have that very same model mr4, and ran it successfully against tc3's. but finally went to the tc3 which I still have today.
The tc3 was a lot more stable and durable. it also had the shaft drive which gave it punch in the infield.
I think with a few updates the old mr4 would will be a good club car today,
New batteries, maybe a 19t motor or a hot stock motor like a cobalt, new tires rp30's and a strutus body of course. an LRP esc, I still have mine today it's over 8 yrs old.
have a blast.