180KB? I only see jQuery (70KB uncompressed, it should be gzipped down to ~20KB) and the 2KB plugin on the demo page.
So that's about 22KB for this effect when most sites already are including jQuery anyway.
I'm actually impressed by this type of UI. Each button is equidistant from the center. This makes it a little bit easier to use for users lacking fine motor control (elderly, disabled, children).