If you're wanting to get better at reading sheet music you really should not have notes being shown. It will be harder to read but that just means you need to start simpler and build up over time. If you get used to reading notes it will always be a crutch you have to work with, and instead of sight-reading the notes themselves you'll be more accustomed to sight-reading the letters.
You might be right about that. I still find though that the most daunting part about learning something new for me is grinding through writing the notes in on the sheet music then "sounding it out" going back and forth from my computer/ipod/ipad getting the timing right. This tool seems to wrap it all up into one neat learning process, perhaps one day after using it enough with "notes on" I could uncheck that box and go pure sight reading.
