Okay, have been intensely trying both the Leon and Prime.
Initial thoughts: Do NOT like the Leon
1. Battery life. Less than half the Samsung
2. Sound quality and BT connection, not as good as Samsung
3. Buttons, soft, and the three buttons on the back: terrible. Unnatural location. Too difficult to fondle and press the "on" button buried between the up and down buttons. Often the small turn on button doesn't work unless one presses down and up
4. Samsung screen has a brighter whiter white
5. Leon had two dropped calls today, Samsung none.
6. WiFi tethering didn't work on the Leon, but did on the Samsung.
7. Samsung faster getting to websites and refreshing
8. Perhaps more comparisons and contrasts to added soon.
The absence of a side button(s), absence of a real front home button,. and the presence of those three back buttons alone were deal breakers.