I have one. It is the hottest warmest coat I've ever worn. Completely brilliant when its Baltic outside, but sweltering for the autumn. I hardly wore it last year as the weather was relatively mild, but it was fantastic the year before when there was lots of snow. I consider it a proper winter coat and feel I'm unlikely to ever need to buy another one, whereas I buy a new "autumn" coat every year or two.
I agree a S probably best for sleeve length, nothing worse than a freezing cold gap between glove and coat!
Had mine 3 years plus now, I am 5ft, it has seen me through many a cold long walk to school and back in all kinds of weather in the North of Scotland (down to minus 15 on one particularly memorable afternoon). Mine has never leaked, and it has plenty of good Scottish downpours. I am sure it is meant to be waterproof but, tech specs and customer reviews here.
Very very warm! I usually end up unbuttoning mine even on a cold morning as it holds your own body heat in amazingly. Never had a problem with the waterproofing either. I'm an 8 and have an XS which is very fitted. If you want the length get the S, the sizes seem fairly small anyway so you wouldn't be swimming in it and it's cut quite close to the body.