Cambridge Airport airport has so few movements that it hardly needs any local air traffic control anyway! There have been loads of attempts to operate scheduled flights from there but most of them have been doomed to failure. (All scheduled flights ended for a while in 2006 but they resumed a couple of years ago). It's so close to Stansted (from where Ryanair have 8 flights per day to Dublin) that it's hard for airlines to compete out of Cambridge.
The main use of Cambridge Airport is for flying schools, for aircraft servicing (because there are soom good facilities there) and for private flights (particularly for jockeys and horse-owners getting to and from Newmarket).
However it's really easy to get to, as it's just a few minutes from Jn 35 of the A14. (Don't even consider accessing it from any other direction though. You could get stuck in Cambridge traffic for hours!). Like most small airports, the check-in and security processing times are minimal. (I've not used it myself but I've dropped people off there for CityJet flights).
Most other local airports of a similar size (e.g. Ipswich) closed down years ago but Cambridge has the backing of the massive Marshall's group. They own all of the land in that area, which explains why there are dealerships for almost every brand of car sold in the UK (all owned by Marshalls) lined up for about half a mile on the opposite side of the road to the airport.
If it's particularly convenient for you I can think of no reason why you shouldn't use it but, given that Ryanair's Stansted to Dublin flights are usually available for £39.98 return, I'd be surprised if it's your cheapest option.