The worst piece of news from the teardown - the whole screen assembly of the Nexus 5 is glued together, and it won't be a very cheap replacement if you drop your Nexus 5 face down to a nefarious surface, so we'd advise to put a protector on, but other than that the whole teardown was smooth sailing...
Source: http://www.phonearena.com/news/Nexus-5-teardown-marks-nice-810-repairability-score-just-dont-drop-it-face-down_id49070
Source: http://www.phonearena.com/news/Nexus-5-teardown-marks-nice-810-repairability-score-just-dont-drop-it-face-down_id49070