What are the pros and cons of submitting to a Preprint server?
The classical answer for that is:
Pro: More people are able to read your work, they are able to read it earlier, you will most likely reach more readers.
Contra: It might not always be beneficial to publish too soon, e.g. if your paper is just an introduction to a big, ongoing project, you might not want too many people to suddenly start working on the same project and maybe publish important results before you do. Furthermore, some journals might not allow it, so check that first.

Whenever such questions come up, there is always a little debate about whether or not it is good to upload to preprint archives. The base line of these discussions can be summarized as "Both sides have good arguments and things might strongly differ between different fields." Thus, you need to decide for yourself if you want to do it or not.