I would say if you can afford them - get them, it gives you a record of what did or didn't happen.Just had one fitted by the dealer on my new car after my son writing the car off -airbags deployed I am thinking of getting my other car done which is older are they any good ?
I chose the direct to the ignitions type ......plus sawdust ....... lol
Halfords fit them, but the reviews are not that great ...... flat batteries etc plus they do it in 2 hours front & back from your ignition ...?
Some, probably all nowadays, record sound, spoken out loud NSFW comments might come back to haunt you