I have played this game for about 4 months now and I have to say I am enjoying it very much. What I like the most about it is that you can make a "party" and play with your friends. This option gave many many in-game hours of fun to my husband and me and obviously finishing quests is a lot easier if you're not going alone. There's plenty of different classes to choose from and after level 20 you get even more options because every class splits into some sort of sub-class (normally there is 4 or 5 of them). The game allows you to have 12 characters at the same time so you can switch between them any time you want if you get bored. I like the variety of skills that characters have, each one unique and (for me at least) interesting to watch :-)
If I had to say something negative about it, it would be very small inventory space but somehow between your personal inventory, warehouse and guild warehouse (if you are a member of one), you manage. Sometimes it takes a couple of tries to actually log into game but I'm more than willing to overlook that considering it doesn't take long to log back in and you get hours and hours of fun once you're in.
Even though I played for months I have very little hours on record purely because I was too lazy to look into it and see why is steam not recording. A couple of days ago I looked around a little bit and found out that if you run steam as an administrator on initial launch it will record hours and show you as "in-game" . Steam did not record hours because the game has it's own launcher and apparently this is also the case with other games that have their own launcher.
Game is free to play although there are in-game items you can buy through "cash shop" with Wcoins (you top up on your webzen account) but in my experience it is not essential for winning to buy anything, therefore I would have to say it is not pay to win, but that's just my opinion. If you are willing to spend some cash, you can get adorable pets that follow you around and have their own abilities or boost your own. You buy "mysterious egg" so you can't actually choose your pet, drops are completely random.
I like everything about this game, from characters and their attractive attire to crafting and many other perks and options. I would recommend this game to anyone.