Give me a reason to switch to Vim from Sublime/Atom?

If you enjoy to punish yourself do it.

Nope

I really like Atom but what are the pro's of Vim?

you can ssh into any box and have the same interface...
never touch your mouse again..
be an el337 hax0r..

They all have their place. Vim is excellent for viewing/editing large files (e.g. gigabytes).

I program Ruby with Vim, Java with Intellij. In Intellij I use Vim bindings to get bindings that don't break my wrist.

@azanebrain only if you have your vimrc and plug-ins there, plug-ins from NFS are sooooo slow...

it opens up instantaneously.

use both! vim is great to check very large files and to work in remote boxes and sublime is very comfortable and has a lot of productivity plugins that help you get the most out of your local env.

vim is more effective for languages like Python, Ruby, Bash and so on (something which is not C#/Java)
i use it. it works great for me. totally advise it to you. you'll be amazed how fast it becomes.

@ozelentsov oh rly? Why is that? How you manage to go through rails project easily? Ctrl+p and nerd tree are just way behind sublime features (like goto any symbol in project xtrl+shift+r)

@alkuzad there are plugins for your needs..it is a trade off of vim but its mode-action-movement-count system is special thing about Vim. i am not sure about ruby, I've just heard about a lot of Ruby programmers using vim. so i apologize if it doesn't work for you, whatever i say is just opinion based. but python+vim works for me just great..