Any European experience with BatteryBrain?

I am seriously considering this; seems like a respectable company based on the FAQ, etc. My biggest concern was what would happen if the thing were to disconnect if the process of switching the car on were to take the voltage to below the threshold of 11.8V, but the below says there's a 30 second delay so that somewhat allays my concerns.

But any real world experience with this in Europe or anywhere else?

"The Battery Brain will disconnect your battery automatically if it detects your battery voltage has fallen below 11.8V, continuously for 30 seconds. This will allow you enough charge to start your motor . Battery Brain is responsible for preventing the deep cycling of your battery which will prematurely end the battery’s life . Gold Utility’s threshold is 10.5 V."
From:
Frequently asked questions about Battery Brain and how it works

 

Under normal day-today operations, what you say holds true.

But, there are many tales on this site of the parasitic drain from the Smart Key system and such draining the 12V down when left parked at the airport and such and the battery rendered damaged/unrecoverable either due to excessive current applied in a jumpstart or the subsequent charging by the Prius charging system. Not to speak of dome lights and such left on inadvertently.

Some thing like the above seems like it would serve to:

1. Not leave the driver stranded
2. Protect the battery or at least serve as a warning for replacing the battery if there are no obvious reasons for the disconnect to have happened to begin with.