There will not be a 8x network load. All nodes behind the same /24 subnet of public IPs are treated as a one big node for customers’ uploads, but as a separate ones for downloads, audits, repairs and online checks: we want to be decentralized as much as possible.
This would allow also to avoid RAID, because it may fail as well:
But in case of even 2 HDDs failures, you could lost only 2/8 of the common data unlike the case with the failed RAID and one big node where you will lose all.