This subject comes up a lot. Live valve models differ in 2 ways: active suspension control, and factory launch mode. Launch mode can be added via a tune, so don't consider that a buying factor. The Live Valve computer is also capable of recognizing the vehicle becoming airborne and will automatically fully stiffen the shocks until your landing is complete. One other thing to note is this version of Fox Live Valve can only control compression and not rebound. Cam-Am recently debuted SmartShox from Fox and features both compression and rebound control.
If you drive a Live Valve model, especially at high speeds, you will notice the computer exerting active body control. This effect is less noticeable at lower speeds, but does offer a "set it and forget it" comfortable ride control for trails, it will also help "auto-level" the machine especially on off-camber trails. It is still recommended to send off your shocks to a professional service for tuning, even with Live Valve. At the minimum, you still need to replace the nitrogen caps with high volume leak-proof caps. Read about it here.
No matter how much work you put into the suspension of a Standard model, you will NEVER get the benefit of active chassis control. Live Valve cannot be added on later...when buying, choose wisely!
An alternative to Live Valve is having a standard model fitted with a Fox iQS system, which allows on-the-fly suspension adjustments. However, at the price of an iQS fitment, you are better off buying a Live Valve from the get-go.
Non Live Valve models feature standard 3 position Fox QS3 shocks. Nothing is notable about these shocks, the fronts on X models are 2.0 while all LV and R shocks are 2.5's.