Fantastic. Have to work around some links, particularly images, so I have it disabled for private windows and open problem links in a new private window.

Unfortunately, the design trolls at reddit no longer have the old-new reddit apparently available, so this no longer works, forcing their awful new look on everyone that doesn't use the clunky old reddit. But when it did (or does again) it was marvelous.

In general pretty good, and a great way to save us from the abomination that is the newest Reddit redesign!
At the moment it seems a bit to broad with what it redirects, maybe you could exclude some URLs / subdomains? E.g. picture links don't work correctly as these are served from i.reddit.com and opening their URL tries to redirect to www.reddit.com/media and produces an error. (and I assume videos on v.reddit.com will fail in the same way).

Can't praise this enough. Urgh the new new layout looks horrendous. If I wanted to view a mobile like site I'd use a mobile device!