Hi Wendy - I've just started FS, so I don't have any experiences with the issues you've raised. I expect, though, that by the time I meet my goal, I probably will have sagging skin and breasts! Even if everything sags, I figure that not carrying around the extra weight will be worth the unsightly sags. I'd rather be alive with saggy skin than dead at a young age because of weight related issues. Besides, won't we be drop-dead gorgeous!?
Good luck!