RE: lookin at buying a LOSI FIVE=T
a kill switch is the first thing you need to buy and install...
once the motors are tuned they stay tuned, not like a nitro, so if down the road it starts losing tune don't fiddle with the needles...it'll be something else. make sure the gas cap has good venting, buddie's 5 here had a plugged hole so started starving of fuel and running lean...best option is to vent the cap with a dubro barb fitting and a piece of looped fuel line.
other than that you should be good...i personally would check all the screws, nuts and bolts etc are tight and anything in alloy is loctited