Welcome
Here is my 2 pence.....
I think the interior is better
Yes you will have pay more tax
Some parts are more expensive..... such as Air filters/Pop Chargers (as there are two needed) HFC's also seem to be more
I think its worth it, and that is from some one who has the uprev (296) not the 313. So I get to pay more tax and have the better interior..... but not the extra horses...... but still more than the pre-facelift