You are fine don't worry about a measly 10% difference.
I bought an external hard drive here in Japan and will be returning back to the states soon. I was wondering if my hard drive will fry if I use it in the states with the 10v difference? I know that this question has came up with Japanese playstations that have the same "Japan use only" warning on them, yet Japanese PS's seem to work fine without a step down converter.
I'm I just being paranoid about losing my files or will the 10v difference really kill my drive?
Thanks very much for all your input.