For a strong 2wd, I definitely WOULD recommend an RB5. I ran one for a while with the Cliff=RC ali bulkhead and the thing was a tank! The casting seems to be to higher tolerances than the AE (Thunder Tiger) stuff and as a result, a crash that would break the AE arms didn't phase the Kyosho at all! I can only directly compare these two 2wd cars but for me the RB5 seems way stronger than the B4. JMO of course.
