I've played Guild Wars since it was released, so I'll try to give you a fair overview of it.
The Good things:
- no monthly fees
- quick and easy to dive into the action, join some people or use computer henchmen to help you
- not intensive if you don't want it to be. You can do a mission, a small quest, or just farm around and chat with people.
- not as hardcore as some other MMORPGs (e.g. World of Warcraft). Levels are capped at 20. The game focuses more on acquiring and using skills. It is more about strategy than a grinding experience.
- you don't have to play both PvP and PvE if you don't want to. You can only focus on one.
- Nice graphics, relatively smooth gameplay.
- You can continually redistribute your attributes in towns and try out different weapon / skill combinations.
The Bad things:
- Very basic chat system. Cannot invite other players by right clicking and selecting invite. A hassle for missions that require healers as you need to look around and find them quick or else they get invited into other groups.
- Weak trading system. No Auction House like the one in World of Warcraft, where you can search / bid on items. No common marketplace setting where players can display their items for sale.
- Not enough character slots. Each account only allows you to make 4 characters. I think we should have 8.
- Not enough storage / bank account space. Basically, your bank box in the game gives you 12 slots for items. Even if you have 4 characters, you still only have 12 slots in total. As a result one of my characters is basically a pack mule.
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Note: The game is instanced, meaning when you go out for quests and missions you can only see players in your party. Some see this as a good thing, others see it as a bad thing. Personally, I don't really mind either way.
If you've more questions feel free to post them.
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I would rate it 8.5 out of 10. In my opinion, the bad points about the game are not so terrible that it makes the game not worth playing.
Let me know if you get the game, I can help you with quests and missions when I am on.