In the writing challenge we are asked to translate: "The Spanish guitar has 6 strings and consists of a wooden box, a neck and a fretboard". Kwiziq's answer is given as "La guitarra española tiene 6 cuerdas y está formada por una caja de madera, un mástil y un diapasón"  and "está hecha de una caja..." is given as an alternative answer. 

I used consistir en instead of estar formada por  or está hecha de. However, if the sentence had been "The Spanish guitar is made of..." I'm pretty sure I would have gone with está hecha de.

So, is my answer wrong? Or, could my answer be considered a third alternative? And could you explain the differences between the two forms, consistir en and estar formado por/estar hecha de, and in what contexts I might use one in preference to another.

Saludos