Hey Keira
Amazing Video.
Couple of things here.
1. Monitors behind him......He is playing solo here so there is all probability that none of the guitar is coming through those monitors. They might be there for other performers in the evenings program. I know that classical musicians generally do not like amplified monitoring and prefer to hear acoustically only.
2. The microphone he is using is a high end instrument condenser mic. He has probably gone through the same process you are undertaking now to find the right mic for the application.
There is the AKG C451B, a very good...but expensive instrument microphone which is probably similar to the DPA he is using.
http://www.akg.com/site/products/powerslave,id,223,pid,223,nodeid,2,_language,EN.html
There is also the Shure SM-81, similar to the AKG and DPA.
http://www.shure.com/ProAudio/Products/WiredMicrophones/us_pro_SM81-LC_content
i see this and i think that mic'ing is the way to go...cos in my test the other day the mic'd sound was definitely more natural than any line out..... and the condenser mic placed outside ...again is superior to the internal condenser,,, and i loved the idea that just leaning in a tad bosted the signal and pulling back but a few mm would soften the sound but not lose the tone..
One thing with classical guitar.....it ALWAYS sounds better externally mic'ed than using either direct or internal mic'ing.
I am busy going down the same route at the moment with my brother-in-law with his flamenco playing....
So Keire....the quest continues....... ? ?