I also have the HD800, m903, and the amazing KH120 monitors. Am also in the market for a tube amp and I was able to recently audition both the Super 7 and BA with the m903. IMO, both tube amps clearly better the m903's headphone amp, which is no slouch. There is more bass extension, more soundstage, more presence, just simply more musical and more enjoyable. The difference between the S7 and BA for me was less pronounced. The BA just does everything slightly better, maybe 5%-10% pretty sure the law of diminishing returns kicks in strong here. I don't think you can go wrong either way but I'm waiting to set up an audition of the Stratus before I make a final decision on which way to go.