You're right, CentOS 7 default file system is XFS. I actually thought it was ext4.
Things are even better. They're willing to apply the SLA credit to a dedicated server! So, I can basically get one of these servers for $20ish for the first month. Winner, winner, chicken dinner!
RAID 0 vs RAID 1 - Difference and Comparison | Diffen RAID 0: Great For Benchmarks, Not So Much In The Real World How did you test raid 0 vs raid 1?