I've moved your topic to the community forums. Please understand this is not a pre-sales question that can be answered by the team, but a matter of opinion that needs to be answered by the community. Asking the team which is better is going to give you an obviously biased opinion as we'd never down-sale our product or up-sell anyone elses.
Regarding the API that's completely false. All of our plugins are extending CB using API. No idea what they mean by the activity stream not being dynamic but our stream works perfectly fine, has API to add new activity, and can even use CB Auto Actions to add new activity on any CB trigger. You can completely demo CB and all our products below to see for your self.
demo.cbdemosites.com/