Before you choose *any* server. Go to the site ARRstatus.com; note down the IP addresses of the lobby servers, and then the world servers you might consider. Then from your PC/Mac, or from a PC/Mac on the same LAN as your PlayStation Either ping or tracert the lobby server(s) and world server(s) at about the time of day you normally play.

The ping/tracert times will be your guide. Do this one a weekday and at the weekend, checking several times on each occasion, and take the average of the response times as your best guidance on a world with less lag for you. Worlds within the same data center are likely to have the same ping/tracert responses, so you only need to try one per data center.

Theoretically the JP 'data centers' as SE calls them are actually one physical data center in JP, split into several server groups. The same is true of the NA 'data centers'. The EU data center is the only one where there is a single 'data center' or server group at the physical data center location. Either way, you only need to look at the lobby server(s) and one world in each geographical location to get a feel for your likely lag issues. Obviously shorter response times are better.