I would really love to know how you guys are changing the pressure of your cases since it's not possible unless it's air tight and you're using a pump. Does nobody know how a fan works? Fans work by creating pressure differences of either side of the fan, the side with the low pressure is the side the air blows towards. Now we all know moving air is slightly lower in pressure than sitting air so if you have a strong current of air in your case then you have slightly lower pressure than the room it's in. But other than that it's not possible for fans to create low or high pressure. Nor does it matter if it's done via intake or exaust fans. Seriously, just stop and think about what you're saying. A fan cannot keep air out of a system nor can it push air into it, it just changes the pressure over the fins of the fan blades to cause the air to move in the desired direction. It cant change the pressure of the things around it.
Now if you are restricting intake then you will strain your exaust fans. The same is true for restricting exaust. But, you cannot restrict this flow by having a weaker fan or less fans on either side. Assuming the case is pretty much sealed except for the fan holes. If you had massive exaust and less so for the intake, then you'd be killing your intake because the exaust fans would be causing a flow of air in the direction the intake fan is trying to blow already. This means there is less resistance for the intake fan to rotate ( moving air == lower pressure) so it spins faster than it should and aids the breakdown of it's berrings. If you must have intake and exaust fans make sure they're far apart and have other openings in the case in places that do not wreck the flow of air you want to relieve strain on either your intake or exaust fans. Having both intake and exaust is actually bad because it's redundent. Only because you dont use ducts and it's hard to direct the air that is brought into the computer do we use intake fans at all. If you're going to use both though make sure you have another area of the case where air can freely enter and contribute to the flow of air you want or you'll just be killing some fans.
lease reaply again to the real poll now that its up:. 
