Connecting them to Wi-Fi does affect the battery life and reliability of the IQR-PG.
The main panel has a battery backup to keep the main panel running for 24 hours. The IQR-PG can also run for about 24 hours when on PowerG if there is a power outage. If the IQR-PG is connected via Wi-Fi, then the running time on battery decreases to about 6 hours.
Also, it will rely on your Wi-Fi to keep running. If switching, I would recommend you install a UPS(Uninterruptible Power Supply) on your router and modem to keep it running incase of a power outage.
If you would like to change over to Wi-Fi, it will need to be deleted, the IQR-PG will need to be defaulted, and then learned back in.
Let us know if you have any additional questions
Thank you