My tip for the top is to not bank on finding any shops when you need them, as there is nothing on the west side, apart from the seasonal cafe at the golf course at Tormore.
If I was doing it again, I'd definitely go clockwise, as the south side is up and down the whole time and pretty draining when you have run out of food and energy. At least there is a shop in Lochranza to buy some sugar at before hitting the last big hill if you go round with the sun.
Its not so bad with weekend Summer season now in force. My advice is to go in the direction where you have a tailwind on the west side. For information, clockwise is smaller hills then the last biggie and vice versa for anti clockwise. If were going clockwise the brekkie on the boat is good and then you have the cafe Steven talks about. Anti and you have a burger shed at Lochranza and shops at Whiting bay.