From my first hand customer experience, my review is: Truly awful service, shady and exploitive business practices, and an all-around terrible experience. Spend your money elsewhere.
Update: Here's what I personally found shady and exploitive from my experience with a Groupon package: (Groupon has since refunded the remainder of my package and apologized for my terrible experience as a client of Mint Laser Clinic.)
Shady: offering additional 'cash only' packages in person and avoiding charging and remitting HST. Another word for that is illegal.
Exploitive: re-negotiating higher rates and packages while the client is undressed and in the middle of treatment.
I attempted to offer feedback on two separate occasions, once in person immediately following a treatment and again on the telephone while attempting to schedule another with a different technician. I was rudely rebuffed on both occasions -- and hung up on the second and last time.
From my personal, first hand experience, Mint Laser's representative should spend less time attempting to have unflattering reviews deleted from Yelp and more time addressing her business' glaring client relations deficiencies.