There is very little evidence that compression garments improve final outcome after any type of lipo. That being said they definitely reduce swelling if worn for the first couple weeks of surgery (if the surgeon uses open drainage). They also tend to make patients more comfortable and decrease the likelihood of dizziness during the first few days after the procedure.
After about two weeks you have probably gotten the most use out of your garment that you are going to get. In fact garments that are too tight can actually prolong healing times because they crush the tiny lymphatic vessels trying to take fluid and damaged tissue out of the wound site. To get the best results make sure that you have close follow-up and start getting post surgical massage therapy about twice a week starting 10-14 days after your procedure.