Bettermpgtoday.com has a rating of 4.0 stars from 1 review, indicating that most customers are generally satisfied with their purchases.
Install and tuning support was a HUGE help. Saw 24% increase in mileage using BMPG6 and Maxim on my Nissan. This guy knows his stuff. Maxim is a great product. Will purchase again soon for Volvo. Thank you MPGMike.