Thanks for the clarifications and the link, Julien! Do the .GPX files include speed accuracy (sAcc)? Even if they do, that is not a typical field in GPX files, so some GPS programs may not read it (the same will likely be true for conversion programs like GPSBabel).
For GPSTC, we really want the speed accuracy numbers so that bad data can be automatically identified. Therefore it would be great if you could add an option to your utility to export in .ubx format. Theoretically, .sbp or .sbn would also be good (even better until ka72.com supports .ubx files), but sAcc would need to be limited to the smaller range in the Locosys formats.
BTW, I'd love to get my hands on a unit, and would be perfectly happy to do side-by-side comparisons against GW-52s and GW-60s. I've got a bit of experience there

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