Depends on your definition of highly stripped, decent replication, performance or bugfixes.
If you don't pay Symas money then no, you won't get support, or bugfixes developed for you.
However I doubt there is a large performance difference, it's already very efficient so it would be in the single percentage points.
As for replication you can do almost anything with the open-source version by combining syncrepl/delta-syncrepl into the topology you want, hell you can do N-way multi-master if you wanted.
I'm not sure what you have against using open-source OpenLDAP, maybe you should try it first?
The open-source edition is only a facade with highly stripped features.
If you want any decent replication, HA, performances or bugfix. You have to pay for their OpenLDAP gold edition, which last I checked was $100k for a site license.