Really, just depends on the person in my opinion. Steam has a MUCH bigger game library compared to Epic Games, even though Epic Games is MUCH newer than Steam, and has already taken over Steam in terms of the companies' value. Epic Games was recently valued at just shy of $30 Billion, where as Steam is sitting at a much more humble $10 Billion. Personally, both companies have their pros and cons, like Epic is constantly giving out free games every week, and Steam has a lot of games on sale at a time. It's just a matter of time until Steam becomes a thing of the past.