Works great if you have the following:

Content worth consuming.

Content worth subscribing to consume.

A production pipeline that can put out enough enjoyable premium content for users. If its good, people will subscribe just to get access to a certain feature or series ala Giantbomb.

Giantbomb has this down pat- but it's taken years of content creation, and a CBS buyout to keep the doors open.

What it can do is make you pretty damn appealing when you go up for sale, if you have the active, paying subscriber base.

That's why Giantbomb is still around and is seemingly surrounded by the of corpses of those who tried the subscription model, but simply couldnt keep subscribers subscribing.