It really depends on your own taste. If you can't stand the storm being even a tad slow, you would do more hard resets. When I first got the storm, I would do a pull mid-day or whenever the memory drops below 30mb. Unfortunately, the reboot time takes a long time, so after a while I stopped doing the reset altogether. If you're like most storm owners, your storm will automatically restart by itself (which is the same thing as a hard reset except you don't have a decision in it)