I have been using the MM CGM (with the paradigm pump) since February and I really like the CGM. I received my first A1C in the 5's% and can attribute this largely to the CGM and TUD. The CGM can be a great tool, but it is not perfect and has a big learning curve. I recently posted about how and where I wear my sensor here: http://www.tudiabetes.org/forum/topics/help-with-minimed-medtronic-....
Some other advice I would give you is to play with your lower level and upper level limits. For instance, I had my lower level set at 80 and when I went hypo I would often drop somewhat quickly. Therefore, when my sensor hit 80, my BG was often 58-66. I found this to be too low. I raised my sensor's lower limit to 81 and now it usually alerts me of a low when my BG is 66-72. Also, as you begin to understand and work with the CGM better I would recomend that you drop your upper limit. Over a 2-3 month period I slowly dropped my upper limit from 200 to 180 to 165, etc. and now have my upper limit at 135. I might only keep my sensor under 135 for a whole day maybe once every 5 weeks, but I like to know when my BG is climbing.
I would also recomend you use the predictive low/high alert. They are surprisingly accurate unless you just bolused or ate. I have my predictive low set for 15 minutes. If I act when my pump alerts me of an upcomming low and treat the impending hypo I can sometimes keep my BG above 70 the whole time. Tightening limits and using predictive alarms causes my pump to vibrate at me many times throughout the day, but it also has led to the best control I have had in my adult life.