I too installed iOS 9.3 Beta 1 on my iPad 2 (64 GB Wi-Fi + GSM) and am finding performance to be improved overall compared to iOS 9.2. Considering the iPad 2 is relatively ancient, I am pleased that it continues to be stable and to adequately perform functions where needed. Slow yes but useable. My iPad mini 2 and iPad Air 2 on other hand are super fast and stable on iOS 9.2.