‘Good Tango’ is very subjective. Because your idea of ‘good’ and someone else’s idea of ‘good’ are based on their experience, and a built (or created) appreciation for what you’ve been taught.

Learning Castellano
Learning to speak and write in Spanish can be lots of fun. Doing so can really force you to understand that your own language is really wacky, that it is fully of colloquial phrases that when translated is a literal mess of confusion, and furthermore forces you to really start looking at your own culture and choices. However when it comes to Argentine Tango, and ultimately going to Buenos Aires, the question comes up … “Do you really need to learn to speak Spanish ?”