Well, with crafting at least. 50% exceptional chance on woodland gauntlets. I craft 10 in a row, none are exceptional. I've also had a streak of 9 non-exceptional and 7 non-exceptional. Those are just since I started keeping track. Edit: Change that 10-streak to 18. I crafted EIGHTEEN non-exceptional gloves in a row with a 50% chance. Wtf? At least the 19th gave me the resists I needed. Time to enhance and get a property I don't want!