Had missed that guide, found most on my own. Still useful, thanks!
In general:
I'd say that it is more dependent on the recording than on the store, and whether the source & process is identified in the notes.
I also personally buy them more for the (hoped for...) quality of the recording rather than being DSD or even HD in any format. If I can still get a decent recording on good old CD, I'm perfectly OK with it. I have a couple of overlapping albums (i.e. HD & lossless from a well-mastered CD) and I can honestly, in the real-world, not hear any "night & day" differences, like some people claim, that would in any way reduce my enjoyment of the music. Especially when it comes pop/rock which you asked about. I find the more notable improvements tend to be in the the classical and jazz genres for example.
I now have DACs/DAPs that can handle DSD but not so much for an expected improvement as much as simply to be able to dump/pipe through any purchased material without having to worry about compatibility or conversions. Whether all the above is worth the extra expense over buying the CD for a lossless rip, that's really up to you.
And yes, some stores have been caught selling "HD" albums that were clearly upsampled upon analysis, but it also may well be that is what not their intention as such, they are just reselling the material submitted to them by the studios. So caveat emptor...
Some forums, incl. those at Computer Audiophile will discuss recordings and whether they are genuinely HD, the Dynamic Range Database is still a good place to compare versions of albums, though DR is not everything, the DR Meter is not very accurate for lossy or vinyl rips, and alas sometimes the source is not clearly indicated which makes comparisons difficult.
In particular:
I have downloaded a couple of albums from Acoustic Sounds, for example Band of Horses' Acoustic at the Ryman, which was not available otherwise at the time, and is one of a few DSD mastered records. It's a great album, but all the other version seem fine too. Also for example Getz and Gilberto, a jazz album though, because they clearly indicated that it was newly mastered from the analogue tapes and were honest about the DSD version being sourced from PCM. HD Tracks was not so clear.
I have downloaded quite a few albums from HD Tracks, with varying results, not necessarily their fault. Some, while in HD, were as poorly mastered as the CD releases, so pointless purchases as a result. Some were as expected. Once they pulled an album & re-released it after fixes (free download for those who had bought it already) But for example they also sell Shelby Lynne's Live At McCabe's which I have not found elsewhere, at least not in the usual mass-market places. Yes, it's CD-quality "only" but it's a great album, well recorded, and worth every penny to me.
I have purchased some from Blue Coast Records/Download Now (not much of a mainstream pop/rock outlet though). One album, as WAV files from DSD (since I didn't have a DSD-compatible device at the time) was faulty, with digital clicks throughout on any equipment I own, never got it fixed. I have purchased a couple more as DSD though, and they've been fine.
Hope that helps, but again the take away is that it's more about the individual album than the store you download it from.
