OK, had the 350K for 2 weeks now and really happy overall. I have however got an intermittent problem with the lens, which has happened twice now....

When switching the camera on the image appears OK in the VF. Then, as soon as you press the zoom rocker to zoom in, the image in the VF immediately goes totally out of focus, just a complete blur. You can focus in, but then any slight change in zoom and it immediately goes way out of focus. Also, if you press the zoom rocker to zoom out, it doesn't work at all, the lens will only zoom in. The first time this happened, I disconnected the lens, removed it and refitted it and the problem was gone. It happened again yesterday, and only corrected itself after disconneting the lens again.

Any ideas before I ring Sony Prime Support ?

Have you run the auto back focus? Sounds like something more serious but worth a try.

Yep, tried that.

Not likely, but try flicking your servo on and off, ditto with your macro and autofocus buttons and your push AF button, also looking for signs of dirt/foreign objects. Remove lens cable and check connector for same issues. Are the pins ok? Is it possible the cable is damaged?

Thanks Chris, the problem has occurred again today so tried all your suggestions. Disconnected the lens & reconnected it, but still the problem is apparent. Left it alone for 15 minutes, switched it on and everything is then working as normal ! As I now assume its a more serious problem, I contacted Sony Prime Support who to their credit were very helpful.
They have registered my camera as a 'Dead-on-Arrival' and are sending me a new body and lens....two weeks to wait though !

Ok, good job Carl, pity about the wait but a lot better response than nothing!