So today I booted into an external HDD to run a Tech Tool Pro 6 scan on my computer as I do about once a month. When it got to the SMART scan, it showed that "Spin Up Retry Count" was close to failing Is this something to be concerned about? It is the stock HDD that came with my MacBook in 2009 and I was thinking about replacing it with a SSD. Should I do so, or is this drive safe to continue using? Thanks for any help in advance.