This is the first answer to my own question after getting the LD-250. There was no storm close to my place yet but there were few farther away. General direction was captured quite well! After the storms come closer, I will report back again.
I have a question regarding false positives: the detector triggers to the heater and other unknown sources. Excluding the heater switch ON/OFF, I would get e.g. 10 or 20 (probably) false strikes per day. Does this sound OK or should the detector be silent (0 false strikes)?