SSD Samsung 850 EVO - MBP 13" mid 2012, 8GB RAM, El Capitán

Hi, I have installed my new SSD Samsung 850 EVO in the main bay of my MBP.

I read a lot about the optimization with the SSD but I still have doubts.

Do I need to enable TRIM?

I read El Capitan permits to enable TRIM in third-party SSDs so I don't know if this is a good option for me.

Doesn't have Samsung any Gargage collector?

Anyway, if the community tell me I have to enable, what is the correct way to do it? From Terminal using "trimforce enabled" ?

What can I expect if I enable TRIM?

NOATIME

Chameleon Optimizer doesn't have a version supporting El Capitan so I don't know what is the best option to enable NOATIME.

Turn off "Put hard disks to sleep when possible"

I don't understand the reason to turn off this option. I read this from Apple Support. OS X: Saving energy with Sleep - Apple Support

I understand this option only works with HD but I according to Apple is not a problem with SSD.

This Energy Saver setting powers down the hard drive motor when you aren't reading or writing files from the drive. This setting only works with computers that use mechanical hard drive mechanisms to store data. Consider deselecting this option if you are using an application that works better with continued read and write access to the hard disk, such as a pro audio or video editing app.

Note: Solid-state drives (SSD) do not use a motorized mechanism to read or write data. For Mac computers that only include a built-in solid-state drive, this setting does not affect the built-in drive. It only applies to externally connected, mechanical drives.

Thanks!