Ah, the world of pirated porn: one in which people are constantly getting their hands on dirty adult entertainment without so much as paying a single penny. Now of course, I hope that none of my readers are in the group of people that engage in this type of activity, so in the assumption of good faith, I will understand if you download site rips because you've created an account but just want a convenient way to access it all.
If that's your desire, then Site-Rip.org might be able to help. It describes itself as the #1 site rip community on the Internet, and with thousands of paysites that have had all of their content downloaded and archived for you to download, I can't really argue with them.
To download the site rips, you use a file hosting service called NitroFlare. Chances are because the site is so large, you're going to want to get a premium account in order to have unlimited access to the porn. I guess that's the way that Site-Rip.org makes their money, because who ever profited from giving porn away for free, right?