Sam, I have had my IS200(SE NAV AUTO) 5 or so weeks and its fab, I was a bit worried on Tuesday as my car went in for 3 new tyres (back to dealer) and they lent me a new IS250 and it was superb, the real dogs bollards, and I thought oh no whats it going to be like when I get back in my 200 but when I picked my car up this morning I thought na this is still an awsome car and handles like a dream, the 250 was quick , but I think the 200 feels like a firmer motor, having said that the 250 will still be on my wish list when I come to upgrade in a few years, but for now I am still loving the 200.
Enjoy it............. and 1 tip, find the cheapest petrol station, you will be there alot. :D :D , mind you even the bad MPG is worth it :) :) :) :) :)