Sprint's Spark Phones Don't Support Simultaneous Voice/Data
However, LTE together with CDMA can. With future Sprint handsets offering all these, the option is still there.
Those that want super fast data "or" clear voice calls, will benefit through Spark. Those that want simultaneous mutitasking such as Voice and Data, I believe the handsets will default to LTE and CDMA allowing the option.
If I'm correct in this thought, data intensive groups that seek just data will not effect those that want to do both due to freeing up needless spectrum for this group and still allowing respectable speed. This is a win for Sprint consumers that no other carrier would be able to offer.
Again, if I'm correct, Not even AT&T's carrier aggregation will compare to Sprint's.
Someone feel free to correct my thought on this if I'm wrong about the way this network is designed to work.