I see. No, this plugin isn't ready for enterprise level environments. PCI compliance (federal law) requires any internet upgrade to 301 redirect changed permalinks as a part of the upgrade process to be compliant. PCI is all about minimizing security risks and disruptions to service.I couldn't get a change control to even test it. It shows promise too :(
Please reconsider your position... I can't use the product as is. I'm betting most other enterprise level clients can't as well.
Lastly it makes no sense for things to be painful for legacy users (real supporters) versus new users. We are your base and it is very responsible to make any upgrade process easy and safe. It seems only new users can enjoy your product without adversely affecting their environment. Your current structure, destroys SEO, authority, inbound, links, and ultimately would destroy the Google Pagerank for upgrading websites. A site like ours which is only events posted in blog form would be utterly devastated. Your plugin would make upgrading event promoters harder to find. Hopefully the developer will think about this.