You need to think about what you want and get that. We can suggest all we want on here but hey, we're not the ones buying it. ARO is like 3 dollars insurance. I run it and that is all I'm going to say to avoid another "should i use ARO threads". You can read all the reasoning
here
http://www.rcuniverse.com/forum/m_5240773/tm.htm And about your how smooth for an onroad question. IT should be flat. these things only have little tires so at high speed it'll flip.