The disadvantages of just a ‘chipped key’ are the inconvenience compared to remote central locking, and the vehicle many not deadlock (depending on vehicle). Some vehicles such as some Renaults only have a door lock on the passenger side which can be rather annoying after a while. Additionally some vehicles will not arm the alarm unless the remote is used. EU and US vehicles will normally silence an alarm once the key is turned in the ignition. Asian vehicles often will not silence the alarm unless the remote is used.
In the example below the customer’s car only came with 1 transponder key (also known as a chipped key). They wanted a remote. They chose this bright green version. This particular make of remote can be programmed to become several thousand different car remotes.