With beta 8, things seemed better at first, but then it’s almost like the Mail app is susceptible to wear and tear - the more I use it, the buggier and less stable it becomes. It only started crashing after sending emails today (something which hasn't occurred since the early betas). I’m really flummoxed. But one thing is clear, at least for me, this has categorically been the worst/buggiest/least stable developer beta run ever - I didn’t think they could top the iOS 7 developer beta phase, but they sure managed. Well done Timmy and Co.