It depends on which country you are, for example, "bacano" is more used in South American countries like Argentina, Chile, Ecuador, Colombia. But "chevere" is more common in Central American countries like Mexico, Guatemala, Panama, El salvador, etc.

Bacano y Chevere son igual de utilizadas en Colombia. Por lo menos en Bogotá

Sally, are you referring to guay (guey or as the sometimes shorten it wey)? That is a very common Mexican word referring to someone as man or dude. What's up man? Que onda wey?

And of course neither in Spain (unless you hang with a South American crowd like I did). Guay or chulo are common there.

Both are used in Ecuador