I have been using this for the past 3 years to augment cheeks and minimize under eye bags with very good results. The affects are instant and last about a year. I didn't bruise (and I bruise pretty easily), and found discomfort during the procedure to be minimal; my doctor uses a topical anesthetic which helps a lot! I think you really could do this over your lunch hour, provided you don't bruise! But Radiesse gets expensive-$695 per syringe. The only bad thing about it is it doesn't last-for me, about 9-12 months.
Now, I am planning to move on to fat grafting, done by a plastic surgeon. According to my surgeon, fat grafting will produce results similar to Radiesse, but will last much longer. (The surgeon said he normally recommends patients try Radiesse first, to see if you like the result). The price of fat grafting ($2800) is about the same as 4 syringes of Radiesse!