On the first part, what amp are you trying those tubes in? At some point this year I'm going to try to keep track of what works where in the 6n1p Schiit family, I'm building up a hoard of novals and will try to post results of what works on Folkvangr, Freya N, possibly upcoming Valhalla 3 (if it wins a shootout against Pietus Maximus for me), and the upcoming Stjarna. All the standard 6922 stuff, and 12a_7 types will be tried.
On second part, the 2/64 was a little more fatiguing on the upper end for me (kind of like mm2). Tubes downline, and Lokius could tame it, but when I went back it felt like putting on a shirt out of the dryer.
I suspect at this point, if there were to be trials, those who like detail retrieval, solid state components, planar headphones, etc, you may be inclined to like the 2/64, Yggy OG/Mib, etc, and if you like warmth, like tubes, etc, you may be inclined to like BF2 OG, Yggy LIM. This is just my guess based on what I've tried, and not a hard and fast rule. I blame my (still mild) tinnitus ha.
Yggy LIM is not warm... My opinion.