That upload speed is tremendous compared to Comcast's regular offerings. How is your latency compared to Comcast? How is your overall experience compared to Comcast during periods of likely congestion?
Comcast worked quite well in my neighborhood. I always received the speed I was being charged for. The TMobile service isn’t quite as reliable, but it’s still quite good. I spend a lot of time on video calls and never have any issues even during high usage times.