Go with a new server.

It will have server opening events, you'll be more on par with everyone.

Will have a better/easier time getting into groups and the sorts.

Overall, it will offer a better experience then joining one of the earlt servers.

Im on S1, and people come in, new, try to start groups and such, but it doesn't work out as there is an establishment of the top already, and to go into a server like that so late into things, its going to be very hard on you.