Whilst I agree with all the comments on the Bridgestones, which VW really should stop supplying, but to be honest I'm terrified with the GTD wheels having a diamond cut face on its outer edge, that this will be damaged when the tyres are replaced.
I always seem to have very bad luck with alloy damage during a tyre change over the years, and wonder if there's anything I as the owner could do to protect the rims during the tyre change process (I.e. Masking the edges of the wheels with detailing tape etc) ?
Or am I just being paranoid ? 
I don't think you're being paranoid. I'll be in the position of needing to get some new tyres some time this year, and I'm also concerned about my un-marked wheels getting damaged.
There are a few places that have touchless tyre changing machines, which minimises the risk of damage, but I think they are few and far between.
http://m.youtube.com/watch?v=j0Hx_rpdxJYSome owners also take photos of their wheels, and get the manager of the place they're getting their new tyres fitted to agree the condition of the wheels before the new tyres are fitted, so if wheel is damaged while fitting a new tyre, the fitting company can't say 'it was already damaged sir before we fitted the tyre'.
It might be worth investigating whether there are any aftermarket alloy wheel / tyre suppliers, who would hopefully have some decent equipment, and staff who understand the susceptibility of diamond cut alloys to damage, so would treat them with care, unlike some of the national tyre fitting chains, who I certainly wouldn't use.