In defence of "free to play": About a year ago, the developers had to build it's own launcher and business model because Steam removed it due to a bogus copyright claim. Now that Steam has relisted the game, the simplest way to get the Steam version into the hands of people that already bought the game was to make it "free to play", and give people the access they already paid for in-game.

About the free version: You get one character slot, meaning you can only play one class at a time (you can delete a character and create a new one if you're not digging your current class). You can only run normal dungeons ( this a more casual "unranked" mode in which you can only use gear or a rarity up to common). This means thar any gear you find in raid above that rarity can be worn in that raid only and cannot be brought into future raids. This might sound very limiting but there are alot of full game owners that only play "Normals" and avoid the more stressful, more tryhard, more difficult High Roller dungeons.

The game is fricking awesome and you'll be hard pressed to find reviews that criticse the game itself. Ignore the idiots complaining that the game is not free enough and give it a try