The OLS, the lowest-cost option, is both open-source hardware and open-source software. This is the product of a cooperative effort between Dangerous Prototypes and the Gadget Factory. To me, being open-source is not necessarily a plus. While it is great to know that I can modify the code or hardware if needed, I am not likely to do so. At the same time, though, I find that open-source products are pushing companies to reinvest in their stale product lines to make them better.
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