Our MGE servers are fitted for this kind of matches. Although the skill level there is quite high You can find em here: http://www.lethal-zone.eu/servers.php
You can take every class. But most guys play Demo or Soldier. It's actually a 'training'-server for competitive TF2.
The only classes available on both of the LZ-MGE servers are Scout, Soldier, Demo and Sniper. There are some MGE servers where every class is available (84.200.5.109:27015). But the most important classes for competitive practice are indeed the ones, you can chose on LZ's MGE servers Hope i could help
No Woody, some classes are blocked. This would include: Pyro, Medic, Heavy, Engy and Spy. It was my intention to let MGE#1 be with restrictions and MGE#2 without, but I keep forgetting to see if I can change it.