consumer-grade IMUs are still well below the performance of even much older military-grade IMUs (which tend to be impressive feats of precision engineering with

consumer-grade IMUs are still well below the performance of even much older military-grade IMUs (which tend to be impressive feats of precision engineering with pricetags to match, but also physically much larger). You'll still find anything that's useful for working out position over any time period is export-controlled (dual-use or stricter).