RB951951G-2HnDConcurrent Connections.

RouterOS Beginner Basics
1

Hi, i have a rb951g-2HnD, and the plan is to use it to provide internet connectivity to 150 users at a conference.

My setup is basic and will work like this:

ports1-4 will be used for load balancing between 4 internet connections, and port 5 will go to network switch with 4 Ubiquiti Nanostations which will be setup as AP`s.

Will this handle all the users?

2

You have not mentioned approximate traffic.
RouterBOARD 951G throughput tests results are here,
http://routerboard.com/RB951G-2HnD
Correct configuration and relative traffic should allow 951G to handle 150 users.