Shark recommends only using one mode per day, as multiple sessions can increase the chances of dry skin or hyperpigmentation. Having previously used CurrentBody’s LED mask that doesn't have this feature, I found it really useful—particularly for keeping track of where my session was at. While I have used LED masks lying down, I found the CryoGlow to sit a bit too heavy for that. (As LED masks have a battery, make sure you never pack it in your checked luggage.) The fans are quite loud when using the cooling pads though, and having cooling switched on does have a pretty big impact on battery life (it charges via USB-C into the handset).