Having over 1000km on the EC70AX wheelset i can confidently say its a great deal! Having used premium wheelset (ENVE G23 and EC90AX). The only difference is the EC70 are about 90 grams more.
That being said the EC70 having 28 spokes is a more robust wheelset compared to others. So if durability is of concern the EC70AX is bomb proof
This is my first set of carbon wheels and the weight, strength, rolling resistance is phenomenal. This was a huge upgrade over the stock wheelset that came with my Cervelo and saved 500+ grams. I bought open box so the price could not be beat.