Doctor prescribed me Metformin to assist with weight loss. Thoughts/advice?

Hey gang. I went to my doctor the other day to follow up on some test results and received some dope news. My lipids, kidney function, cholesterol are all normal, and my a1c is 6.8%! I have had diabetes for 14 years and this is the first time it has ever been under 7 so I am super happy about that! The only thing my doctor mentioned is that I need to get my weight down. My diet is pretty good, and I have been losing weight, but I'm still about 40 lbs overweight so he prescribed me Metformin to help. What do you guys think about that? Pros/cons? I haven't started it yet although I have the prescription filled and ready to go.