@rlkoshak You are faster with edit than I with response. 
Probably solution by group can be better that I can freely add/remove switches to group, without altering rule.
Is there difference in terms of speed? As I want raspberry underclocked to stay cold.
Now I must look how to solve “SwitchWeb” in e.g. HABDroid, if I want to see on one line current light state and control to toggle it.
So, what if I put into the group only SwitchUpstairs, SwitchDownstairs. In site map I will have only StairwayLight, and write rule only to toggle?:
rule "StairwayLight"
when
Item gStairwayLight received update
then
if(StairwayLight.state == ON)
sendCommand(StairwayLight, OFF)
else
sendCommand(StairwayLight, ON)
end
Or is this totally wrong idea?