Car audio is, like most technologies, a rapidly changing field; what is trailblazing today can be outdated and redundant quite a short space of time. However, an outdated car audio system is still very much a functioning one, and so the user should not get too preoccupied with having the newest system. More important is whether the unit will function in your car, its compatibility and suitability with your requirements, and how easy it will be to get the system up and running; whether this is done by yourself or a professional.
Getting the unit in the car and ready to set up is the first hurdle, and is an important factor. Many cars today have moulded units that are difficult to remove or alter, and require tools that the average user doesn’t have. For this reason, it’s worth checking to see if your car requires a plastic faceplate adapter; if it does, these are available from any large online car audio specialist, or for aftermarket versions, eBay. In addition to the adaptation of your unit, many audio systems will require a ‘bridge’ consisting of wire and pin adapters; manufacturers hate buyers putting their own audio systems in, and will often create a complex system. However, this is easily overcome for a small amount of money.
Lastly; does the unit do what you want it to do? As well as playing CDs and having an FM radio, will it support bluetooth connectivity, run your phone through an auxillary cable, or have a hands free kit for conversations on the go? These are often easily overlooked but can mean the difference between the ultimate car audio system or a redundant piece of machinery.