ok well if you're debating between a side exhaust and a rear exhaust....
almost all 1+ hp engine are rear exhaust. so if yo'ure gonna get a new powerful engine soon, mine as well as get the rear exhaust kit now and save yourself the money down the road.
i use a starter box for my side exhaust CV-R. the advantages and uses of a starter box are so plentyful. for example, my starter box will start my engine whether it wants to or not. my ofna box comes with a powerpanel with a connected glow plug starter, so there's 1 less thing to charge. and because i'm using a 12v battery in my starter box, i can charge my rx pack & tx pack using my superbrain and alligator clips. so if you're in a pinch, just charge your 12v battery and deal with the rx and tx pack later.
hope this helped. BTW the starter box i have is the Ofna 1/10 with accesories. it has 2 540 motors and comes with a 12v battery and powerpanel/glow starter. it's $85 at tower.