[NiLuJe]

@perisiana: You're saying the bit that's taking long is *saving* the percentages in Calibre's Library, not *pulling* them from the device?

(FWIW, my setup is everything automatic, with manual validation needed for actual update in Calibre, and both steps take a few seconds at best, even on the H2O. Granted, I'm nowhere near even a thousand books on device. And everything's KePub, in case that matters. And my column setup is fairly low key (basically, the reading % would be the most complex bits, because I have one for Kindles, one for Kobos, and both are used to compute a third one).).