In your case, it should not be a problem. Since there are 3 intake fans and only one exhaust at the back, it would create positive pressure within the cabinet (more cfm of air being sucked in than what's being pushed out). Usually, this is the preferred air flow configuration of most people. But since your front panel only has provision to draw air from the side vents, it could potentially affect this ideal scenario. To make sure that's not the case, perform the incense test by holding a couple of lit incense sticks close to all the vents. First hold the sticks close to the front panel and make sure that the smoke is being pulled in by the fans. Also make sure that the exhaust fans are pushing the smoke away from the fans. Finally, hold them near all the vents (back of the case as well as the top). If air is being pushed out of all these vents you're all good. You have a positive pressure system going on. If air is being sucked in through any of the vents, it's an indication of negative pressure and you might need to increase the rpm of your front panel fans to overcome that.