I havent played the one for psp, but I did play tactics ogre for ps1.  I LOVED IT 

  Its a ton harder than most tactics games (including FFT) since once your characters die, theyre gone.  You dont get a few turns to try to finish enemies before the corpses are gone, theyre just dead.  You can get a revive late in the game, which is nice, and it definitely makes one appreciate that ability more than in most rpgs.  I also like how most/all of the classes have a 'specialty' weapon where their attack animation changes to something cooler (valkyries with spears ftw), and theres a lot of neat ways to earn unique classes (like lich).  I should have probably asked this first to confirm, but is the psp tactics ogre title a remake/revamp of the ps1 tactics ogre like FFT -> FFT war of the lions?