I wouldn't use it all the time since max rotation on the fans does mean more wear and tear on the bearings, but if you do it once and you see a dust cloud blast out the back, you need to find a way to keep it cleaner.
Dust around your console(s), wipe them down with a dust cloth once a week, use a can of compressed air to blast out anything that collects inside the case, etc.
One important thing about the compressed air; only use it when your console is cool (not during or immediately after playing). Compressed air is very cold. When you rapidly cool down a chipset that's been running hot, it is entirely possible for something to crack (solder joints) while contracting during the rapid temperature drop.
If you're too lazy or forgetful to do this, that's fine, but it's kind of like changing the oil in your car. If you don't, don't be surprised when your engine finally breaks down and seizes.







