Antonio, but that's only if you don't buy the monthly bono (which I guess tourists or short term visitors wouldn't)
Go Madrid, besides the cercanias, there are also ample busses from madrid to alcorcon (so if you're going to be there past 11pm when the train stops, you'll have to opt for the bus anyway!)
The metro sur is just going to add on to the great transportation we have for alcorcon and those extra cities!
Soooooo happy!