I have a Mac mini mid-2010 that has been suffering from extremely slow performance for sometime (spinning beach balls with the simplest of applications, slow to open web pages or applications, etc.). I made an appointment with the Genius Bar fearing a failing hard drive. I also ordered memory to max it out to 8GB. I installed the memory today and there has been a notable difference in operating speed. Do I still keep my service appointment to make sure that it wasn't also a failing hard drive? Time isn't a real factor since the Apple Store is close by.