Most of the pull-to-refresh plugins or concepts I saw had drawbacks - some emulated native scroll with JS (seems slower and non-native to me), others (mobile gmail) hid scrollbar altogether, others made scrollbar appear as if some content is already scrolled.
As no available app seemed good enough for me and project requirements required iOS only, I drafted this.
Basically, everything what needs to be hardware accelerated, is actually accelerated.
The testcase seems to perform quite well on all my target platforms - iPhone4, 4s and 5.