Disclaimer: My blogs are not a reflection of my employer's opinions, but are my own, and often unfiltered. Also, some links on this site may be part of an Amazon Associates program, so by clicking on them you help me pay for my independence.
[[{"type":"media","view_mode":"media_preview","fid":"25","link_text":null,"attributes":{"alt":"Acquia Certified Developer","title":"I am an Acquia Certified Developer","height":147,"width":147,"style":"width: 60px; height: 60px;","class":"media-image media-element file-media-preview"}}]] [[{"type":"media","view_mode":"media_preview","fid":"15","link_text":null,"attributes":{"height":180,"width":180,"style":"width: 60px; height: 60px;","class":"media-image media-element file-media-preview"}}]] 
[[{"type":"media","view_mode":"media_original","fid":"13","link_text":null,"attributes":{"height":68,"width":310,"style":"width: 190px; height: 42px;","class":"media-image media-element file-media-original"}}]] 
This module allows you to grant access for specific user roles to view unpublished nodes of a specific type. Access control is quite granular in this regard.
Additionally, using this module does not require any modifications to your existing URL structure.