they are an excellent choice, can be run in std trim out the box but is recemmended that you fit bearings as they come with bushes as std.
the std idler gears can last a while, depends on motor choise and driving style also if you throttle it, when stuck..
the std shock bodies would need upgrading eventually too as the tops can pop off, you can get cheap shocks off the bay or upgrade the shock bodies to the X spec..
hope this info helps..
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