Thanks all for your replies. I really appreciate it. I had the latest beta of iOS 9, beta 3 I think (not 9.1) and it was unusable. The downgrade process was a nightmare. I run Linux Mint as my OS and Apple doesn't make it easy for us even though their own OS is Unix based as well. One can't even downgrade using Virtual Box running Windows. I think it has something to do with the virtualized USB drivers or something. Anyway, I really appreciate all of the feedback. I want to have a good idea of the probability of success before deciding whether to take the plunge.I recently clean installed an iPad 2, then last week put iOS 9.1PB on it. It was unusable. Downgraded to 8.4.1 and it was much better. A few days ago, updated to iOS 9.0. My initial thoughts was it actually felt faster. I'm gonna check it against another one running 7.1.1 next week.