I'm pretty "underwhelmed" by mine as well. I know it's just a fan without any active cooling, but I think it "sucks" air through the perforations in the seat (as opposed to blowing) Check the vents behind the seatback when it's running, if something is blocking them the airflow is significantly reduced.

 

dr_joe is right, the seats pull air from their surface instead of blowing cooled air. they have their advantages...in high heat, when the seat surface is hot i think they work better than seats that blow cool air. i've found that with those systems a hot seat will actually warm the air before it reaches my body and for a good while i have warm air blowing on me from the seats. eventually they do end up getting very cool though.