I'm using HDR Efex Pro v1.2 as a plugin to CS6. It has 32 'Presets' (grouped into realistic, artistic, surreal, landscape, etc) and a 'Custom' option. There's no mention of a 'Default' option.
I'm using ProPhoto RGB in NX2 & CS6. I always convert to 16 bit TIFF when leaving NX2 for more pp in CS6.
(BTW the camera is shooting in Adobe RGB).