Hi there -
Our son Sam has a parotid hemangioma that we treated with steroids for three months (about 6 weeks at full dose and 6 weeks weaning) starting when he was 7 months old. He's now just over a year. Based on our experience, here are a few answers:
1) We saw change in Sam's hemangioma within a few days as well. In his case, the deep part went away almost completely after about a month or so and we haven't seen noticeable rebound growth at all. He's been weaned almost 2 months.
2) We were also worried about the effects of the meds and only time will tell if there are any long-term impacts. Sam wasn't much fussier, but he barely slept for many weeks. It was really really hard - he would literally sleep for an hour or an hour and a half at a stretch and then be up for an hour to two hours - all night. That was the only problematic side effect and it began to resolve (as did the huge cheeks and the weight gain) about half way through the weaning process.
3) I think that the steroids vrs. surgery question is so different for every situation that it's hard to say. For us, given the inherent risks with any surgery and the excellent outcome we had with the steroids, I think we did the right thing. Our own doctor felt strongly that Sam was not a candidate for surgery although we did send some photos to other doctors in the US (we are in Canada) who disagreed. A lot of posters here suggest following your instincts - unfortunately my instincts said something different from minute to minute. I decided that we needed to trust our doctor and try what I felt to be the least intervention possible first. Your mileage may vary.
4) Don't know the first thing about cryotherapy but I'm sure someone here will.
Best of luck!