Just keep your digital gear & SMPS type psus and walwarts AWAY from your analog gear. That is all you need to do. They may affect your analog gear but they will have NO effect on your digital stuffThis is actually inaccurate. The power supply on digital equipment, including digital transports such as streamers or disc players, will defintiely impact the sound quality. If you cannot hear a difference on this it means your listening skills and/or hearing are not as sensitive as others or your audio system does not have enough resolution to reveal these differences.
I've been reading this thread. I think the OP has a good point on this product for an alternative to the really cheap small 3" x 3" wal-warts that come with a lot of our audio equipment. Of course, this will not be as good as a nice linear power supply (which he has said), but it should give a good improvement over this small wal-warts. For $50 you can get a nice improvement, but for $250-800 you can get the top end linear power supply. It all depends on how much you want to spend and how important it is to you.