My only and biggest complaint was getting terrible network speeds (like 1Mbps)

For this verizon roaming phone, the phone almost always reported "4G" and "LTE" with fast data speeds.

The speed was very fast and the call and text were seamless

I think the remaining of the 52 countries would have even worse speed or inconsistent data connections.

even when phone read as 3g i had much faster speeds than US 3g.

During an overnight stay in Amsterdam, however, I noticed much better connection speeds