From previous runs I found that archive/validation were pretty much limited by CPU, with signatures at ~85%, signature hashing at ~5% (this machine does not have shani) and block read/populate at ~10%. There's a little to shave off there in reading, and of course the NET/archival is already fully optimal. That completes in around 4.5 hours (no confirmation). Which means that confirmation on the maxi is only about 30 minutes of the total 4.9 hour cost. I could probably cook up a theoretical limit for validation based on signature/hash cost, but I think it's probably around 3.5 hours, plus the 40 minutes of download. Puts us pretty close to optimal (for this hardware).