I think these are good choices. In lieu of tracking down unreleased 5.1 mixes, vintage quad recordings that were only released on vinyl and Q8 are the second best option. I am enjoying the recent Best of Guess Who release, but a DVD-A conversion from the original quad reel sounds pretty damn good, so not a huge leap in having a better sounding version of that release. With the titles that only came out on vinyl and 8-track, there is more room for improvement.