I have been playing a PsyWar for a while as well (level 8 right now) and one thing about them is they are limited as Piratecat noted, but its very heavily influenced by the number of fighters per game day and the ability to read your DM.
My character mainly only uses 30-40hp vigors and expansions in fights with all other powers being situational or being left off to converse power points. This leaves him good for about 3 fights a day. But the capability is there to pull out all the stops and dominate a fight, leaving him weak for the rest of the day. This situational tuning abilty when you know your DMs style so you can use powers in preparation can make them very powerful. Playing with the tuning does make them a very fun class to run and as I'm the only tank Im not overshadowing anyone.
They are definately up in the top rung of classes as written, with only the cleric being ahead. Maybe.
My character mainly only uses 30-40hp vigors and expansions in fights with all other powers being situational or being left off to converse power points. This leaves him good for about 3 fights a day. But the capability is there to pull out all the stops and dominate a fight, leaving him weak for the rest of the day. This situational tuning abilty when you know your DMs style so you can use powers in preparation can make them very powerful. Playing with the tuning does make them a very fun class to run and as I'm the only tank Im not overshadowing anyone.

They are definately up in the top rung of classes as written, with only the cleric being ahead. Maybe.