Berlin Marathon is a great event! Greatly organized, course is fantastically flat and aid stations very well placed and loved the cold bananas! Access extremely easy from anywhere with the amazing Berlin transport system! On top of that the city is great and offers a lot at very reasonable prices!
Only gripe we all have is the lack of a t-shirt... would rather pay more for entry but need a t-shirt that even the race in the villages provides...
Apart from that... definitely a must!

New York New York! One of the most amazing cities in the world and the best marathon I have run so far! Getting to the start is a bit of a nightmare .... but once you start definitely worth it with amazing views over the city !!! Great T-shirt and SWAG, management and organisation (it better be for the price paid for entry! :)
Once I finish the Majors I might do it again! Not easy and pretty hilly.... Strongly suggest reading the book (available as audiobook too) "A Race Like No Other: 26.2 Miles Through the Streets of New York" before heading there.... great insight of the race!