Often we get asked what Server Class a region is. In the past there have been different designations for server types, from class 4 (the very early stage of Second Life) to class 8 (the latest, fastest server type). Customers often think they have to ask smart questions to get the best and fastest land on the fastest server.
Linden Lab has moved away from that sort of server designation years ago but the rumor that there are slower and faster server types in Second Life does still exist. Server class no longer matters because Linden Lab has created a system where each region is allocated the same amount of resources as others of its type ( Full Prim Sim, Homestead, Openspace ) .
There is a blog post on it here: https://community.secondlife.com/t5/Land-and-Sea-General/Moving-away-from-server-Class/ba-p/650813
So, in short words: Since 2009 already, there are NO server classes anymore. Often landlords claim to have all their regions hosted on the latest server class but there is simply no such thing anymore and they are just trying to impress their customers by giving false statement. ALL regions in Second Life are allocated the same amount of resources as others of its type.