I have been getting Restalyne injections for 'marionette lines' around my nose and mouth for about 3 years now, and the last time I went the doctor put a tiny bit in my upper lip to fill out some fine lines there. I abolutely LOVE the results. I go when they have a '2 for 1' special (one syringe is $750), as I need a lot on one side of my face. I go for two syringes once a year, and then maybe for another touch up 6 months later.
Lately I have not had to go for touch ups as the effect is cumulative to a degree. Mostly the pain is minimal- although around the lips is a very sensitive area and some of the injections do hurt, the pain goes away very quickly. There is swelling after the treatment, particularly around the lips. I looked like a duck after getting my lips injected. That took about 3 days to go away.
There is also bruising, but arnica ointment minimizes this and promotes faster healing. The down side is that you get used to the way your face looks with the injections and unfortunately the results aren't permanent. But if you go to a good doctor and get the right amount of filler, the effects will last at least 6 months and probably longer. At least that has been my experience.