What is the difference? Can I get more range out of Z-Wave plus over Z-Wave?
Z-Wave Plus can offer improved battery life, faster operation, and better RF coverage (range) over that of standard Z-Wave devices of the same type. This would require both the Z-Wave device and the Controller to support Z-Wave Plus.
Z-Wave Plus products are also backward compatible with classic Z-Wave products. So should you have a panel with a Z-Wave radio you can utilize devices with Z-Wave Plus certification (and vice versa) but the added Plus benefits won’t be available.
If current Z-Wave range is an issue, a few more repeating nodes in your mesh network may be more cost effective than replacing all devices with Z-Wave Plus.