I never had a Blackberry but everyone I know who did says it was the best phone they ever had.
Having said that, I am not sure they could have withstood the app revolution without participating in. I do think they made major mistakes in their strategy at critical points, but simply focusing on their core business demographic might not have been enough. The get corporate IT on board, IIRC, you had to run a Blackberry Enterprise Server (?) for security and corporate connectedness. This was not cheap. That was becoming increasingly problematic as the iPhone and Android infrastructures caught up security-wise. In the end the cost to maintain the Blackberry servers was no longer justifiable as many people wanted the shiny new phones with all the apps.
You’re right about the BES requirement but they could have easily gone SAAS-optional when the industry shifted to the cloud.
I found it to be way better than the Blackberry. If they had forced me back to the BlackBerry I probably would have found a new job.
And, a huge number of colleagues who saw me using it at work got excited and put in requests for their own iPhones. It was just so much easier and more pleasant to read on the iPhone.