Pins are just something to hold the hood down and anyone could remove it (that is if your CF hood doens't have a latch). Hood locks actually lock your hood down so that nobody could open it (as well as keeping the hood from flying up). I've had a VIS CF hood on my car for over a year and I see no need for pins. Others do it for peace of mind, others get locks for security purposes (they don't want stuff under the hood stolen). It is necessary to get locks if your CF hood has no latch and pins are recommended if the hood does have a latch (in case the latch gives out or something).