Thank you both for taking the time to respond. I've decided to definitely get one, the original 3570.50 version. I love everything about the look of this watch, and the 42mm case is the perfect size for my wrist.
I did look at the slightly cheaper 323.30.40, grey face date, and the 3220.50 day / date, both 40mm cases but I just couldn't get past the look of them. The grey case just doesn't have the same allure as the black moon, and the day / date is just over fussy with dial characters. They felt slightly too small too. I know that buying either just to save a bit of money will have me regretting the decision within a week!
Now I just have to find the best deal, but I have read that some high street stockists are prepared to do a deal on price?
Will post a pic on my 40th B'day in August when I get it!