I've played both, and actually enjoy both, despite the fact that I have quit World of Warcraft and Guild Wars and have not touched them for months now. Generally, Guild Wars is great for a rare-moderate player, who does not have the time to simply level grind. It allows for great flexibility of hours and although is not as indepth as other games, namely World of Warcraft, its a great game in and of itself. There are not many classes, but the combination of skills and flexibility of skills definitely make it feel like you have different combinations. Now for World of Warcraft, I only ended up being level 20 before my account expired. The little I played showed me just how indepth and amazing this game was. Consequently, the game would obviously take more time and effort to max your level. Both games are renowned for their player versus player, although Guild Wars is similar to a deathmatch/ Counter-Strike gameplay while World of Warcraft relies on raids and wars between guilds. All in all it depends on your playstyle and financial capacity. I have not yet played Guild Wars: Factions, nor do I intend to. Best of luck finding a good game for yourself!