Demoed at 1gps speed but 50 to 60 mps expected.
Phones to be released soon to support the speed and software updates to current devices soon after.
" The first Spark-supported phones, Samsung's Galaxy Mega and Galaxy S 4 mini and LG's G2, will be available on Sprint's network on November 8th. Software updates for Samsungs' handsets will enable tri-band "shortly after launch," with a similar update scheduled for early 2014 for the G2. The HTC One Max will also support Spark, but Sprint has yet to announce availability. "
http://www.engadget.com/2013/10/30/s...usaolp00000595