No problem. I only use the best parts since my name is on the line. If you went part number to part number, they are well over what I charge, I know because I visit the sites myself to see whats out there. They also state "Corsair or major brand" for instance on their memory, there are a lot of flavors of memory out there starting at a base price and go up for the same memory, reason is the better and faster memory cost more. If you read their specs and lookup the review's, some of the parts they use do not get the best scores. Investigate the ASETEC 510 C, lots of problems with that and the one fan is usually not enough. Plus my customer service is second to none as those who have invested in a system from me can attest to.
I am sure you will be happy with the system you configured. It should run the game pretty much maxed.
TD