Just somedays ago my colleague and me were deciding to use second hand branded PCs vs custom. So here we have a dicussion on branded vs custom. 

Branded

pros

1. Warranty by brand – call the brand if your pc breaks down
2. Preinstalled just open and run

Cons

1. After warranty if stuff breaks parts might be hard to find
2. Might come with many unwanted software that slows down your Computer

Non branded

Pros

1. Easier to replace parts after warranty
2. Custom your own parts
3. Custom your own software. Install only those you need. 

Cons

1. Have to send in parts for warranty yourself usually
2. Have to decide which parts you want more hassle
3. Have to install Operating system etc before it can run or have someone install for you