I have run in both the Zegama and the Pegasus. The Zegama has a 4mm drop, so if you're used to a 9.5mm drop (like the Pegasus), the Zegama may not work for you.
I just blew through two pair of Zegamas, wearing the toe down to the foam after 125 miles (albeit on the road). I also experienced hamstring pain when the shoes were brand new. Once I wore the lugs off the toe, no more hamstring pain. This happened with both pair of Zegamas.
After reading that a lower drop may cause ankle strain / hamstring pain (especially if you're not used to that), I'm going to switch back to the Pegasus or may even try the Invincible 3. That ZoomX foam is super comfortable.
For what it's worth, I'm 45 and getting back into running. I was a 14:30 5k guy back in the early 2000s when I was running in college. Back then, I ran in the New Balance 850 series and Nike Elites.
I hope this helps.