OVERALL IMPRESSION: I really enjoyed cruising in the Mach Supersonic and would definitely buy this shoe. It felt fast and efficient and is a cost-effective alternative to the plated Rocket X, though it is priced at $150. It felt springy but not spongey. I like the drop at 5 mm, feeling that it is just about right on runs. I question the functionality of the split tail heel for efficient midfoot strikers and also am wondering about the massive heel loop above it.
PROS: The Mach Supersonic may be a transition shoe between the Mach 4 and 5. It is a very light, nicely cushioned version of the Mach and a fun shoe to run in. The Profly+ midsole makes it easy to extend your runs with protection and foot security over the Mach. I like the full outsole construction of rubberized EVA which hopefully enhances the durability of the Mach, which has been known to be easy to beat up along with the Rincon.
CONS: It felt a bit too narrow to me, especially in the midfoot area. I felt like I was spilling outside of the midsole foam. I did not feel this in the Rocket X or Clifton at all.
FIT: The fit is true in length and snug in the midfoot area in width. I do not recommend this to the runner with a slightly wide foot. If still interested, size up a half size to get a little more width. The nicely padded tongue is integrated to the upper via elastic strips so that it snugs the midfoot nicely and stays where it belongs during the run. The slightly elf-like heel collar was nicely padded but not overly so, making it an easy shoe to get on and take off.\
RIDE: This is a very fast shoe. In addition, the ride was a very nice, efficient and fun experience. The shoe is pretty light (8.3 oz advertised - 9.8 oz for a size 12) and rolled well through the transition to push off. The foam was just right to allow an easy push off out of it at the end of the stride. The outsole of rubberized EVA looked durable and showed little scuffing and wear in the miles that I put on it. In addition, the stack was not overdone so I did not feel unstable in it nor did I scuff the bottom of the shoe during subtle road surface changes.
The Mach Supersonic will be available on 3/15/22 and retail for $150.