I had the Valhalla 2, but settled with Vali after a lot of listening. Valhalla 2 won't add much to the bottom end, except for a harder hitting, and tighter impact in the upper bass (still no sub-bass). What I found odd was how some people thought the Vali and Valhalla 2 would be really similar sounding and was confused why I even went with Vali instead. To me they sound very different from each other. Valhalla 2 had a hard hitting impact, especially with drum & bass, to the point of it being fatiguing. The Vali was much more smooth and easier on the ears. Also for a tube amp the Valhalla 2 was very bright, adding sibilance into tracks that wouldn't display it with the Vali. Mainly tracks with female vocals.
Returning the Valhalla 2 and sticking with Vali was a difficult decision, but in the end I'm satisfied I let it go.