tiesto: what smooth groove said -- there should be a REASONABLE chance of you getting good upgrades every hour, and a small chance of getting a fuck awesome upgrade (that will let you fuck shit up for the next 10-20% of the game) over each 3-5 hours of play. also, lots of character customization in terms of skill and equipment, good boss encounters that work well for team play, and a wide variety of interesting skills in general.