Hi SteveH
While I haven't been able to take advantage of the rarified air of a Sky suite just yet I have snuck around a M class ship a bit. There are only 2 small negaives that I know of and would not let them bother me a bit.
The life boat fore of you will block a bit of the straight down view and those guys that are "Pimped" out in the X suite next door to you will have a bit of a view onto your deck. (If they have their curtains open) They have no deck.
the rest is all positive. Great mid ship location. The main elevator bank is across the ship from you and easy access to all over up and down. And of course the room is very nice. & best of all
The martini bar is just one floor down right belwo you.....so it's easy finding your way home.