Has anyone heard of Agent-B for the treatment of Varroa?

This product is produced in Germany and is said to consist of essential oils,
propolis, alcohol and natural acids.  It may not be as efficient as Apistan or
Bayvarol, but it may be less toxic in the production of comb honey.

I would be interested to hear about your experiences of Agent-B, or other
sources of information about it.

Many thanks,

Les Simms.