That’s a very good point about lead times. I can remember some forum members who ordered a mk7 GTI around the time the order books first opened waiting 8 - 10 months or longer for their cars. VW lead times in general don’t seem to have improved - when the current Polo GTI was announced, some owners over on uk-polos.net had a 12+ month wait for their cars, and a few are still waiting 15 months after ordering!

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I’d personally also not be an early adopter of a new model - especially one that’s laden with lots of new tech that could have a number of teething troubles. I wouldn’t want to be one of VW’s unpaid vehicle testers

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Also, based on current spy shots, and forum members comments, the mk8 isn’t as good a looking car as the mk7; being longer, and the bonnet line giving the illusion of the headlights and grille being quite low down, it looks oddly proportioned from some angles. The GTI might look better than the non performance models when VW release official pictures of the mk8 GTI or we see the GTI launch models in the metal, but IMO it’s not a thing of beauty.
If I was contemplating a new GTI now, I’d not wait for a mk8. With the mk7.5 being near the end of its lifecycle, there ought to be some really good deals to be had.
Life’s too short to play the waiting game.