Thanks for the comments. As the back inside tyre was down to 1.9mm (Shock horror) and the fronts wer knackered due to the tracking being out but still has 3-4 mm in the middle I decided to change to a set of part worn 245/40 x 19's Dunlops (I have a business trip to Bradford and Aberdeen this week so did n't want to run therisk of falling foul of the law). Only £60 a go fitted and ballenced. Insurance Co said Ok so I will give them a go this week and let everyone know. Apparently they came off a Jag so are amuch more common tyre.
£1000- 1300 for a set of tyres for 14,000 miles is too much. £3,500 for 3 sets of tyres on a 3 year 45,000 mile contract ! Get it sorted Alfa or I back off to Audi ! My boss wasn't too impressed.