I took the Leon for "proper" drive to work this morning, first time without wife and kids in...
It handled like a

DOG
It's absolutely grand with normal driving and I have grip where I never did before (especially in wet). Much smoother ride and low road noise. Steering feels lighter and feedback is great.
Show it a corner and you feel like you're going to go through your tyre and ride your rim. Like riding on marshmallows and the tyres wail and scream in pain at even the slightest "spirited" corner. BAH!!!
So, once again on this forum I will pay for the lesson so that other people can learn from it as well, and I am once again prize n0b
Do NOT cut corners on anything that FR or above. Saving 25 quid per tyre to not go XL will make your car KAK. 91W non-XL tyres are NOT ok!!!
My fault entirely, nothing wrong with the tyres. They're amazing:
GoodYear F1 Eagle Assym2, 225/45/17 91W. Definitely recommend...if you DON'T have a "sporty" car.