Noisy Inovelli Red Switches? (LZW30-SN)

Why get the GE or Honewell “Aux” switches instead of some Inovelli on/off switches? Will the Inovelli on/off switches work as “Aux” switches? Seems like that would be a cheaper (and better) route if they do.

EDIT*** Looks like I found my own answer. It seems like the recommendation is to use an “Aux” or add on switch an not another smart switch:
" * Neutral Wire Setup: You can choose to have either a dumb (existing) switch or an auxiliary switch. You can also choose to install another Inovelli smart switch on the other side, but there are some limitations here and we do not recommend it at this time."

This may be a dumb question, but If you can use the on/off as an “Aux” in a 3 way with an Inovelli Red dimmer, will the on/off act like a dimmer?