Hi BigButter321
In my experience it is always better to build your own pc for a few reasons ,
1. you can customise it for only the specific parts you need
2. with a bought pc in most cases the components are as cheap as possible so you think you are getting a good deal for a low price
especially power supplies and unknown brand ram and motherboards
3. there is nothing like the satisfaction of building your own rig and having it perform exactly to your needs.
4. it is a great learning curve to build your own pc , its easy and not rocket science , but remember if this is your first time building
google and youtube are your friends , from reviewing a product to how to install a cpu or motherboard etc etc , a little study may save you a lot of headaches , also ask on these forums we are only to willing to help.