Obagi Blue Peel Vs Microdermabrasion Which Will Show Drastic Results in One Session?

Hi everyone! I'm desperatly trying to rid of all my acne scars and sun spots on my face. I have pitted and dark spots from severe acne years before and it still hasn't faded. I am searching for a treatment between Obagi blue peel (TCA chemical peel) and diamond microdermabrasion. Between the two, which will show real results in one session? I'm on a budget enough for one or two. I understand that there should be at least 3-4 but again I'm on a budget and hoping to scruff off even partial!