The zooz z-wave switches are the only ones I've seen that let you wire them into an existing 3 or even 4-way circuit with a single smart switch (leaving the other dumb switches in place). Other smart switches replace the master on the circuit and then you put what are effectively remotes (or actual remotes in the case of Lutron Caseta) to replace the non-master switch.
Second the recommendation for Lutron Caseta if reliability is your #1 concern. Absolutely rock solid, but it involves another hub and the switches are pricey. Don't have any zigbee switch recommendations unfortunately. Sorry.
The zooz z-wave switches are the only ones I've seen that let you wire them into an existing 3 or even 4-way circuit with a single smart switch (leaving the other dumb switches in place). Other smart switches replace the master on the circuit and then you put what are effectively remotes (or actual remotes in the case of Lutron Caseta) to replace the non-master switch.
Second the recommendation for Lutron Caseta if reliability is your #1 concern. Absolutely rock solid, but it involves another hub and the switches are pricey. Don't have any zigbee switch recommendations unfortunately. Sorry.