Do different cargo carriers to the ISS generally have different profiles for their cargo composition, or is it basically just the number of tons that matter? Especially with respect to cargo which is expensive to replace, such as some spare parts and science experiments.
Many different spacecrafts have visited the space station: Proton, Soyuz, Shuttle, ATV (ESA), HTV (JAXA), Progress, Dragon, Cygnus. It was my impression that much more attention given to the experimental payload lost with the Antares/Cygnus Orb-3 failure in October 2014, than after the loss of Progress 59 (or M-29M) in May 2015. Didn't the Progress carry as much value per ton? Or is it maybe a national issue? American Cygnus carrying American payloads which are reported in English speaking media, while Russian Progress carries mostly Russian payloads which are harder to learn about for non-Russian speakers? What factors play into this, technically and policy?