I've got the same thing with a few 'preliminary' quotes I've got....pain in the ass as I'm currently looking for the perfect R32 GTR and have a completely unblemished (cept for 1 $50 6km over speeding fine) record for the last 5 years I've been driving. I'm no angel but I'm not a dumb f**k like some people who speed well over limits.
All the companies I've approached see Twin Turbo and 23yo and shit themselves....might have to try Shannons and see what they say.