At £30k in its basic form, it is competing with a completely different set of peers. The Scirocco R doesn't do much better than the 2.0TSI GT in the used market, but then again it has the achilles heel of only being 2WD, so it doesn't appear to be much better than the remapped GT. GFVs seem to indicate that the R won't hold it's value much better than halfway between a GTI and GTD on a percentage of RRP, and the likelihood of getting less or no discount than can be achieved on a GTI makes it far more expensive to run one over 3 years.
Assuming you can get £3k discount on the GTI, but not the R, and we're talking GFV only after 3 years (it'll be probably a grand more at part ex time if you look after it) then that R will cost you almost £6800 more to buy, but will be worth £2400 more in GFV, so it'll cost you £4400 more to own one over 3 years (not including interest).