As others have said, highly location dependent.

I switched from Xfinity to T-Mobile 4 years ago because tmobiles speed (raw speed) blew Xfinity out of the water…especially for upload. Latency and jitter suffered a bit but not enough to greatly effect voice calls. It didn’t help my online gaming skills, but likely would’ve if I were a higher-caliber gamer.

However Xfinity did some upgrades in my area and the roles have reversed so I’m back to Xfinity. Tmo is still absolutely usable, but Xfinity now offering 250mbps makes my mouth water.