I don't like them, think about it, if your throttle is stuck open you have to take your hand off the bars to cut the engine!!!
Happened to Pol Tarres at Penrith he shot off at max revs & couldn't let go of the bars to operate the lanyard, dangerous.
Is it cheap though?
A top end mountain bike can cost more than a new trials bike today, entry fees can also cost more depending on the event.
I think trials bikes are cheap considering the capabilities of the machine.
Noticed Jack Sheppard's machine looked well worn & was pinking/knocking when I saw it at penrith.
I wonder how much the factory is able to support him?
Assuming you have a 2007 sherco, these are notorious for dodgy stators, one possible early symptom is variable timing. If the timing has momentarily advanced then the engine could run backwards when started.