I have been using this for around 1,000 miles of cycling. I have noticed a lower heart rate and better efforts. I really like the green apple flavor and feel that it helps hydrate me pre-ride as well. I used my wife as a test and she had a lower heart rate during our ride as well. The key is to drink it 20-30 minutes before your effort. Will be using this as a staple for rides.
I have used MFX N.O. for the past two weeks and my experience has only been somewhat satisfactory. The taste (Watermelon) is good, not too sweet and the product mixes well in water. However, taste and mixability are secondary considerations as I am more concerned with a product's effectiveness. That is where MFX N.O. has not worked well for me. I have not experienced any notable increased pumps while using this product. For the first week, I used the recommended serving of 13.7 grams mixed into 12 oz. water about 30 minutes before training. As that resulted in very little effect, I began to slightly increase the amount by one gram at a time and as of today I am using 16 grams with still no noticeable effect, other than a slight increase in tingling from the niacin. Overall I am not very pleased with MFX N.O. but perhaps it is possible this is not a formula that works well for me. A discontinued product that MuscleFeast sold under the name "Primitive Pump" worked fantastically well for me at the recommended serving and I had expectations that this product would work just as well. I don't believe that I will be purchasing this again, however, I do plan to continue purchasing other MuscleFeast products as I believe the quality of their products is better than many other supplement companies.