I had a double mx two years ago and came home on the fourth day - my four drains having been removed gradually over the last two days. My wounds were glued and stitched with dissolving stitches. There was a very sturdy sticking plaster like dressing on top of these which was well stuck down for about a week.
I had failed wle a month before the mx and both times I was lucky enough to have no problems with either infection or seroma.
It seems that there are quite different procedures depending on where you live. I had my surgery in Edinburgh.