Glad that you like Quartzy! We have been working on the product for more than 6 years and are constantly iterating the product based on member feedback, which is one of the main reasons why it works so well!
Unfortunately, for the same reason though, we cannot offer a copy for you to install on your local server. The primary reason is that the site gets updated almost every month! Every month we launch new features, speed updates, tweaks and more which make the site better! So if you installed a local copy you would be stuck with something less than ideal.
Our business model also would not support a local server install since we generate revenue which allows us to develop and support the software and keep it free for use from hosting vendor catalogs, running special deals, and more.