Wireless are rubbish, had to got to so many customers houses to rip out a wireless system to allow a hard wired system to be fitted. Key fobs are pants too, if you go on holiday with the mrs and she takes her keys too nobody can get in to water the plants etc unless you pay for more fobs, a number code is so much easier.
Hard wired can also have a CCTV system added to it, it can call you on your mobile if activated and adding stuff later is almost always compatible.
My parent were advised by their buliders after the '05 floods in Carlisle to have a wireless setup, it died within the first month and still doesn't work. I'd warned them but apparently Shonky builders know more about alarms than somebody who owns a security business.