Currently DCS is pretty unstable, at least yesterday evening it was...
We usually fly the MiG21 but the L39 is seen gladly as well in our group.
It isn't quite a dogfighter, more like a light striker. So we use it on Alpenwolfs Cold War server, or on other servers like Kirks hangar... or on Aerobatics servers, just for fun.
Currently we don't have an own server, since we're still waiting for the dedicated server implementation. So our focus are the mentioned servers. ;)