Had time to sort out my spare key on the way home from work today.
I've had a key transponder from a yaris sitting on my desk ready to use since the start of march, but the first key I got cut only worked in the door once and wouldn't budge in the ignition.
Got a second key cut today for free which is much better. It's a bit stiff going into the doors and gets caught but it opens and locks them perfectly and works in the ignition no problem. Sorted out the central locking and immobiliser coding in five minutes too.
The first key was cut very deep and produced a lip at the shoulder, whilst this new one is a lot closer to the original key although not as smooth.