The best replacement for z wave is insteon.

The best alternatives to z wave are rated as following:
★★★★★  insteon
★★★★  zigbee
★★★★  x10
★★★  wemo
★★  lutron
★★  nest
★★  upb
★  nexia
★  control4
★  lightwaverf
★  control 4
  x 10

Your alternative for z wave is not listed? Suggest!
Speaking about z wave, one probably shouldn't forget about schlage.

Other search terms related to z wave and their ratings are:
★★★★★ schlage
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