Good enough to make you come back for seconds..
The skill system is the most dynamic and flawless aspect of the game, giving you a complete control factor over who your character is, what he does, and removing the whole 'class' farce.
Alchemy provides a way for people to upgrade their items, but as such the quote goes: "With great risk comes great reward". You can do more harm than good with some alchemical equations. In fact, a lot of them.
There is also no 'requirement' to purchase items from the 'item mall', but it does make the day go by a lot quicker when you have a Golden Ticket (doubles your xp, 3 hrs per day, for 1 day [the cheap one] or 28 days [the expensive one]). Unexpected server downtime usually gets you a free one day ticket and time added back on to your monkey (You'd just have to play the game to understand the monkey).
At any rate, it's a good game especially for a Free MMO RPG, and it has a vast landscape to traverse as well as a very well established playerbase. There are some problems getting on servers occasionally, but SRO added one new server last month and has announced another one to be added in early July, so they are working to keep up with the expanded player base.
There are definitely some big upgrades in the works, and the people who wrote the game don't leave me with the impression they are willing to sit and let people spend money on this without providing them with more substance. Not only has this game been out since 2004, but the best really has yet to come.