MAX Br2 Pro for Event with 175 people

Hey all,
I’m going to provide internet access to an event for max. 175 people.
150 People on a Guest Network via WiFi (with external APs from Netgear)
10 Staff (including a stream) via SFC connected by wire and WiFi.

I own a MAX BR2 Pro and would like to use it with 1x internet by cable from the venue and 3x mobile internet (2x internal modem, 1x usb).
People on Guest Network will use the internet mainly for voting via their mobile phones. Means: Most times there will be nothing happening - but than all phones become active at once to make an online vote.

On a datasheet (https://download.peplink.com/resources/peplink_br2_pro_datasheet.pdf) I’ve read that there was a field “Recommended users = 1-150”. Do you think I am good to go with max 175 people in a situation I’ve just described?

Usually I use this device to get me and my stuff internet - distributing internet to about 150 people is new to me.
I am planning to use a /23 subnet with a lease time of 1 or 2 hours for the guest network. And of course a separate VLAN for Staff.
Any other recommendations?

In your experience, how many users can the device manage at the same time? And what are the processes that require the most power?

Kind regards from Germany