All major insurance companies DO NOT have a problem with turbo timers. This has been quoted a few times and I don't know where people get their wrong info from. I've spoken to many companies regarding this issue and not 1 have said they are illegal to use or would they turn down insurance based on this. This includes companies like HIC, Adrian Flux, etc.

To answer your questions, yes and yes. BUT: get a good auto-electrician to fit it and you shouldn't have any problems.