Per discussion today, Denis is seeing frequent failures to download things from DM, ostensibly because the SHA check is failing.

Suggestion is that this is caused by checking the SHA before the whole download is flushed to disk, resulting in frequent download failures at about 98-99% completeness.

https://github.com/redhat-developer-tooling/developer-platform-install/blob/master/browser/model/helpers/downloader.js#L83