Out of the box, the Nimbus 15 looks almost identical to its predecessor. Even the overlay patterns look the same.
The shoe still has a very flexible forefoot, which gives it a fast transition heel-to-toe (maybe too fast). Side-to-side, the shoe is a bit rigid, but its not stable enough to appeal to even a moderate overpronator. A stiff heel counter locks the foot in place.
I had the opportunity to review the Gel Cumulus 15. In that review, I commented that the Cumulus felt at least a half-size too small. I did a side-by-side comparison with the Nimbus, and the Nimbus felt true to size. If you can’t seem to find the correct size in the Cumulus, you may want to try the Nimbus, which I felt had a superior fit.
When I had both the Nimbus and the Cumulus on, I also noticed the difference in Gel cushioning. The Nimbus had noticeably more Gel, especially in the forefoot. Runners who put a lot of stress on the forefoot may want to consider the Nimbus over the Cumulus for that reason.
Another difference between the Nimbus and the Cumulus is the amount of foam throughout the upper. Asics does not hold back when it comes to memory foam in the Nimbus’s upper. In my review of the Cumulus, I commented that the upper was light and breathable. On the flip side, the Nimbus has a fairly substantial upper, which gives it a luxurious feel, but also means it is slightly less breathable and heavier feeling.
- See more at: http://www.runningshoesguru.com/2013/05/asics-gel-nimbus-15-review/#sthash.8CJNLD14.dpuf