The first and best benefit is Information.
A well placed UAV will reveal a large group of enemies at once. There are VERY few people who can ignore nine new blips. Any LRM users will thank you because this way you give a lock and you don't have to "hold" it.
Next benefit C-bills and Experience.
For every mech you detect with a UAV gives you cash and experience. For every person that uses your UAV for indirect fire and do a certain amount of damage, you get an assist C-Bill and Exp bonus. It also breaks ECM and gives you a C-ECM bonus. If you are grinding a mech for exp using the UAV is a great way to speed up the process. Even though the C-Bill pay out is modest it is one of the few consumables that offset their cost reliably.
The last one is Scouting
Use the UAV to look over hills, around buildings, or use it as a kind of sentry. While this is the least beneficial use especially if you detect no enemies. It can save your life. For example you're one of the last mechs left in a conquest match, and you need to avoid dying to win. You can use the UAV to detect pursuit.
So... the downside.
The cost 40,000 C-Bills can be alot to part with each match when you are starting out.
The UAV can be shot out of the sky. It isn't an easy thing to do, it is hard to see and you can't lock onto it, but it can be done.
It requires 30,000 GXP to get the UAV maximized in both range and duration.
It uses up a module slot you may want to be using for something else.
So in the balance of pros verses cons it is totally worth it.
I forgot about the counter ECM bonus Thanks Arnold J Rimmer
Arnold J Rimmer, on 19 December 2013 - 02:19 AM, said:
Edited to add missing facts
Edited by Mao of DC, 25 December 2013 - 05:55 PM.