I hate it when people give reviews like this. If they sound good, then rate the sound well. If they're comfortable, rate the comfort highly. If they fall apart in a month, give them the minimum for design (since that's the closest thing to build quality). You could even rate the value down for that as well since you have to buy new headphones so soon. But don't give them a half-star rating overall just because they broke on you, even if it is a common issue.
Headphone Reviews and Discussion - Head-Fi.org