I discovered this one a couple of weeks ago myself. The content appears to be taken mainly from other websites (including this one). Like most Russian sites, there is no discernible observance of copyright law in any form, so users should be aware (no you can't upload all those Messiaen scores here!). The rather inflated file count for this site (65,000) appears to come from lots of duplicates of the same basic scan. (I discovered 4 files for scan of the ca.1925 Muzgiz score of Mussorgsky's
Night on Bald Mountain, for example - one locked, another with pages cropped, a third with all 8.5 x 11 pages, etc.) The downloads are much faster than Tarakanov, and the site is certainly worth perusing for new and different items (I added a Fürstner piano score of Delibes
Copellia from there yesterday, along with a nicer scan of the Hugel piano score of
Sylvia). There's also a new score search engine site:
http://www.scorser.com