The Nexus 5 is one of the best Android phones on the planet and thus, one of the best smartphone options for Sprint's 4G LTE network.
Google's current Nexus flagship delivers a fantastic design along with a high-resolution full HD display, quad-core Snapdragon 800 processor, 8MP camera with Optical Image Stabilization, and vanilla Android 4.4 KitKat. It offers all of that and an extremely affordable off-contract price tag.
Nexus 6 rumors suggest that we could see a replacement emerge later on this year but rumors point to a release much later, perhaps in October or November which means that this device is still a solid buy. There is also no guarantee that it will come to Sprint.