Theirs has a nice, simple presentation which makes it very easy to use, especially for casual users. But it includes much less information (no confidence interv

Theirs has a nice, simple presentation which makes it very easy to use, especially for casual users. But it includes much less information (no confidence intervals and p-values are only approximate), uses much simpler statistics (z-test with no multiple testing correction can result in highly overconfident results), and doesn't describe what underlying statistics it uses. Although not as immediately accessible, I think Abba has much more to offer to anyone who's serious about A/B testing.