This is just a personal opinion, but I noticed that if I compare my own site to a nearby site (which just happens to be a user that has multiple sites in different geographical locations) and we both share the same nearest airport code, following the link to the other username currently takes me to his default site rather than the site qualified by hash-stats-NNNNN (which represents the “nearby site” comparable to mine).
I’m not saying the figures are wrong, I’m just saying that the username url should have the site that is being compared, purely for consistency. I guess this is not a problem for usernames that only have one site because the hash-stats-NNNN qualification is superfluous.