What are the long term effects of having a BBL?

What are the long term effect of BBL? Some women stated that their butt hurt when sitting for long periods. These are women who had the surgery over a year. Some have said it feels different or like a foreign object when running/exercising. I even had a person tell me it felt heavy when they had to walk up stairs and she had to hold her butt to stop the pain. Are your patients sharing this info? Is this normal for A BBL? And why are some docs using Smart/Vaser for procedure knowing it is wrong.