The user interface here was very simple and uses a very basic template that has been used on many other paysites over the past number of years. Update information was an issue for me - as this site's update schedule is unpredictable, it would be nice to know when future additions are likely to be made to the site. There are no other major problems here that I noticed.
From what I could tell, it doesn't seem as though some of the photo sets were available for ZIP download here although you do get three photo sizes per gallery. All videos can be downloaded in WMV and MP4 format with HD versions available on all videos. They can also be streamed in-browser but there was only one option on these. Each video also comes with a gallery of screenshots - mostly just static butt shots!
Remember back to a couple of years ago when nobody had even heard of the word 'twerk'? Or has it been in common usage for longer? I only became aware of it when Miley Cyrus shook her arse in some video and everyone said she was twerking! And now we have Big Butt Bounce Twerk.com, a site dedicated entirely to models and amateurs doing that exact same thing - and nothing else.
I have to say that it's a curious idea for an 'adult' site on one level because some of these ladies don't even fully bare their butts. The vast majority of them stay clothed too. It feels more like a (mostly) amateur version of World Star Hip-Hop or something like that. Not that it's a bad thing, the videos and photo sets are perfectly fine for what they are and the site doesn't really do anything wrong at all.
Amount of content: 100 videos and 35 photo sets
Update frequency: 1 video every 1 or 2 weeks; photo set updates irregular - usually one every 1 or 2 months
Exclusive content: Yes
Max video resolution: 1280x720px (HD)
Video types: Flash, WMV and MP4 (stream and download)
Photo resolution: 1065x1600px
Available for mobile: Yes