We've never really had a problem... Our sinopia npm server is probably isolating some network problems, plus we don't start/update servers that often.
Our NPM workflow also ensures builds are easy to replicate. Most problems in development occur because of obsolete versions of some packages (our apps contain many private modules)... Clean npm-installs shields us from that in production.
Our first major improvement to this work flow was a tar of the app with all of the dependencies coupled with `npm rebuild` after unpacking. This worked quite well.
However, recently, we have switched to using Docker to generated this sealed packages which is working great.