length at 42mm is about right but bear in mind that is from the tips of the lugs so it wears MUCH smaller so definately worth a closer look if your AD has the same case size in just to see the size on your wrist.
I have just picked up my Grande Sun Moon (thread is on page 1with some great pics if i do say so myself..:o)...!!!) and this from the tips of the lugs is 47mm but you will see from the wrist shot it doesn't look big on my 6 1/2 - 6 3/4" wrist.
I also found the Master Calendar far too big, I was after a moon phase but I am now over the moon (excuse the pun) with my GSM.
Happy hunting,
Andy.