...Actually what's more important is Frame Rate. 720p @ 60 fps looks better than 1080p @ 30fps.
For sports 60 fps is the best. 720p vs 1080p of course 1080p will be better IF the bitrate and encoding is on par. I've seen 1080p streams that look like garbage compared to some 720p streams.
http://ckaratech.com offer plenty of 720p and 1080p channels
I have four IPTV services and they all have 720p 60fps for the majority of the USA channels this is because they are all getting their feeds from PS Vue. If you are using a fire tv device you can check this via. https://developer.amazon.com/docs/fire-tv/system-xray-developer-tools.html . choose advanced options. As previously mentioned this is far better than low bitrate 1080p 25-30 fps, in my experience, 60 fps are so unreliable and short-lived in other packages they are not worth worrying about. The only way you're going to get consistent 60fps sports is via smoothstreams/startstreams and they don't even do 1080p 60fps.