Buy a calibration kit. Just do it. And no, you won't find anything better for the same price (I've tried). I really like this thing, it's very accurate (by NIST calibration) and has around 15-16 hours of write time at the highest bitrate - more if you turn it down a bit. The display is easy to read, the buttons work well and are intuitive to use. The sound in the leaderboard comes from the SOFTWARE. The software is TERRIBLE, illogical and generally difficult to use. Apparently it was rushed to market and unsupported. Just export the entire dataset to Excel and process it manually, it's better that way (good luck with the connection! - you'll end up making money, but be prepared for a bit of a struggle). A tip: Use a very high quality USB cable. Do not use unnecessary or supplied cables. It's readable.
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