Wanting to understand availability [in stock, had to wait, still waiting] , how long it took, problems etc.,

It will be exactly the same as a normal screen, other than plugging a couple of wires in, so expect less than half an hour to cut it out, and about the same to put it back in, plus a couple of hours curing time for the adhesive.

Autoglass availability within 7 days, the actual process takes 2 hours including bonding & curing, you're not to wash the car thereafter for 48 hours - otherwise straightforward at least to the Autoglass guys. I recommend you supply a new set of wipers (I used Bosch A980S Aerotwins - http://www.ebay.co.uk/itm/161579410995 ) at time of fitting, and they'll probably fit them for you.

My experience about a month ago was that took about 4 days to get one into stock (on the South Coast), although when the second technician came to fit it he convinced me, with no great difficulty, that he could repair the original, which he did and arranged the refund of the insurance excess.  A month on and the repair seems to be holding up. 

ok, any experience of National Windscreen service - got hit last night by something coming up the M5, nicely cracked today, Insurer uses <-

I've had heated screens changed on a Focus (twice) and our Mondeo.

 

As above, only difference to a non-heated screen is that there's a couple of wires to connect up.

 

Note that some companies like Autoglass etc use cheaper eastern-European sourced screens. One on my Focus was, yet the one they fitted to the Mondeo was a Pilkington.

 

Both worked, but I did wonder how long the cheapy one would last before heating elements started going. Didn't keep the car much longer after that to find out.

ok, any experience of National Windscreen service - got hit last night by something coming up the M5, nicely cracked today, Insurer uses <-

There ok, they replaced my screen a year or so ago, but they managed to crack the black pastic cover on the passenger a pillar. Needless to say they replaced that FOC.  Don't think much to their chip repair it's no-where near as good autoglass

ok thanks for that ^

update, fitted this am , excellent job, 1 hour max, let you know later if watertight etc!

Pilkington unt to be fitted Friday - thanks for the reminder with regards to wipers - good call .