If I drink anything in the day in Benidorm it is the local Amstel draught as it is pretty harmless. In the evenings I usually drink the green bottle Mahou. If they sell the red stuff then I might buy that instead, because it is a nicer tasting drink, but there is no way I could drink it all night as it is potent stuff! Funny thing is, a lot of places do sell it but don't offer it unless you specifically ask for it.
Nowadays, I'll only drink spirits in places with English bar staff, who understand that I'd rather pay £2 for local spirits and post-mix mixer than £6 for "genuine" spirits and a little bottle, since I can't tell the difference! The Spanish bar staff understand that request perfectly well but are obviously under management orders to screw every last cent out of customers who they expect to sit there all night with one drink! I actually saw the manager in The Town tell off a barmaid who gave me what I asked for!
I also like the Guinness in the Shamrock. I don't normally drink the stuff but it's nice to have something that isn't gassy.