I was always under the impression that flush mount, or hugger, ceiling fans were better because they don't have the "wobble" problem that the traditional ones with a down rod have. "They are mounted flush to the ceiling, so how could they wobble?" I thought. This, however, is not the case.
The real issue here is the quality of the ceiling fan. Some are constructed using lower quality blade materials. In addition, it is important that all blade brackets have the exact degree of pitch, in other words, the same angle. One other important factor is that the blades must be sold in sets that are carefully weighed and balanced. All of these issues, if not correct, can cause your ceiling fan to wobble.
Ceiling Mount Bracket
The real advantage to the flush mount fan comes into play when you have ceilings that are 8 feet high or less, because it is the distance from the fan to the floor that is important. To maximize efficiency, you don't want the fan to be closer than 7 feet from the floor. Therefore, if your ceilings are 8 feet of less, and you add a down rod, the fan would be too close to the floor to get the most out of it. In this case, the flush mount fan is perfect!
The disadvantage of the flush mount fan comes into play when you have ceilings that are higher than 8 feet. In this case, it is best to purchase a fan with a down rod, depending on the height of the ceiling. The following chart, found on Garbe Industries Inc's website, shows the length of the down rod you should use based on the height of your ceilings:
9' - 6" down rod
10' - 12" down rod
12' -24" down rod
14' -36" down rod
16' -48" down rod
18' - 60" down rod
20' - 72" down rod
However, if your ceilings are 8 feet high or less, feel free to enjoy the various flush mount, or hugger, fans available. You will find them to be quite effective if used in this manner.