Radios control things like Cellular, WiFi, Bluetooth, GPS.
Each version has its unique radios.
The software that controls them would tell the device to get HSPDA+ on band x or LTE on band Y.. stuff like that.
For example. ME i have T-Mobile. I have a T-Mobile branded HTC One. For a while i ran my One fully stock GPe with the TMO radios. Why? Because when TMO sent out an update a while back (prior to 4.3) they updated their radios and i saw noticeable improvement on LTE for TMO..
SO naturally when i converted mine to GPe i wanted to keep my TMO radios. The GPe might not have the tweaks to its radios that TMO sent out and at the time the version on my GPe was older. So i put the newer TMO radio on it and i felt like it was working great.
Someone else chime in with pros and cons.
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