Update....well I've done it......I've got rid of the King Cobra, I am such a wastrel with money
In it's place I have got this -
CLICKY
Traded in the Cobra for £120 (£70 hit on this

), luckily sold my old golf clubs last week for £150 - so the new driver has effectively cost me £9.99.
This time I have been custom fitted, and what a difference that makes.
Firstly the lad at Scottsdale Golf made me hit a few balls with the Cobra - straight away he could tell what was wrong. My grip, stance, and clubhead speed were all bob on, but the amount of spin that I was imparting on the ball was stupidly high. He said that a good drive imparts about 3000rpm on a ball - with the Cobra I was consistently getting spin rates of 6000rpm+.

It was this that was causing the balls to erratically hook, low and left. He said that this was not down to the clubhead, but was down to the shaft.
He offered to reshaft the Cobra first, but I explained that I had lost all confidence in it and that I would like a different make. So we tried the new Callaway FT-5 (composite head which was very very light) and the TaylorMade R7 SuperQuad. The Callaway felt too light, whereas the TaylorMade immediately felt good, and the feel of the ball off the face was very very good. Even with the standard shaft in the Taylormade, my spin rate was consistently at 2900-3100. Ball speed was averaging around about 126mph, and trajectory was much better with a higher arc and a much more consistently longer carry - we had changed the loft as well to 11.5, and the shaft weight to 70g (from the 55g Cobra).
He then took a load of further measurements relating to trajectory/load/speed etc...measured my hands so that the grip could be changed, and has emailed all of these off to Taylormade so that the shaft and grip can be custom made. I will get the club within the next 10 days.
I cannot praise
"Scottsdale Golf's" custom fitting service enough - the custom fitting, which took about an hour and a half and the hitting of many balls, was free and I was given refreshments. The lad who fitted me was patient, listened to what was going wrong currently, checked - not only the club - but stance, grip, etc.... He has even thrown in 2 free lessons with video analysis after I get the new driver. I even explained that I already had a Taylormade 3 Wood and that I rarely used it - he told me to go and get it from the car and he would analyse that - the club and shaft were fine, but it was my stance and takeaway which were the problem. All in all, I feel much more confident now about my driving and I would highly recommed anyone to have their next set of clubs custom fit.......
Oh, and I can now look forward to drives without that annoying sound from the "King Cobra"