The best companion

[DGDobrev]

With Agvares, you can put 2 weapons (Singing Dagger and 20% Crit, for example) as a Paladin or a Mage, which will make killing them way faster. With him, you can put on 2 slippery cuirasses, or a slippery cuirass + leather dress. The other artifact slot can be useful because you can slap in +30 mana or an ancient amulet for +4 Int/15 mana, which is great for a Warrior.

As for Gaudi, +50% crit against demons will help greatly in the final battle.

I may be wrong in someone's eyes, but what KBAP taught me well is that flexibility is the key to success.

[Hento]

Too bad you can't have your own castle to leave all your companions in and paying them upkeep each day, if you have more than one.

[DGDobrev]

Well, that would make the game look a lot like HOMM

[Hento]

Nothing wrong with that, some aspects of HOMM5 are very good, like seeing your heroes being actively involved in the battle, some spell effects, fort sieges etc.