So far, so good. 
Well it's been over a week or so, thrown the car round a few corners left and right etc to test, haven't heard the knocking. 
I wonder if it really has been solved by something so simple. 
Well worth giving a go if you're considering it, parts cost under a tenner. 
Decent feedback, thanks Mandy.
Who fitted the parts out of interest?
I was thinking of taking it to my local dealer and saying "I have
that steering problem, can you please address it", but, can I do it confidently or was the recall stuff not applicable to all Mk5 GTI's?
If I'm going to do it, I want to do it confidently with the right info

Mine has disappeared aswell, changed the lower ball joint when I changed the cv gaitor, and my clunk/clink has gone too 
Maybe I missed it, but did you not replace the Subframe Spacer Plates Steve?