I offer my experience in case it is of help. I own a Cordoba C9 Crossover with 59mm string spacing at the bridge and 39/40mm at the nut (48mm nut width). I also own a Cordoba C9, which has the same spacing at the bridge, but 42mm at the nut (52mm nut width). This specifications are standard for classical guitar. For proper classical technique, I find the C9, with its extra spacing at the nut, much more comfortable on the left hand. Also, I am much less prone to inadvertently dampening or buzzing on neighboring strings when playing certain passages. I tell you this because I assumed that coming from playing steel strings for a long time meant that the tighter spacing of the Crossover would be best for me, but I was wrong. The GK has slightly wider string spacing at the nut than the Crossover, but I am not sure that many classical players would find it adequate. One last thing - many on AGF talk about nut width when, in my estimate, the issue is string spacing at the nut. You play the strings, not the nut, and nut slots can and are cut in different ways on the same sized nuts.

I hope this helps.