The same crowd that wants you to believe 16/44.1 sounds the same as 24/96 or 24/192 is the same group that wants us to believe MP3 192 is indistinguishable from CD and therefore 24/96. It is a lot easier to say something, have us believe it and get back to business selling us crummy sounding, cheap, smaller sized 99 cent downloads through iTunes and Amazon.
The only way you will know is to do your own listening and tests. If you hear no difference, then a 99 cent MP3 download will suffice and a 1TB drive will last you forever.
Have I been disappointed in some high res downloads? Hell yes. The Doobie Brothers Long Train Running sounds absolutely dreadful. But they are few and far between.
Here is a possible experiment to try: buy "Hope" by Hugh Masakela on CD, SACD and Vinyl. I did. It's no contest. The vinyl is 10 times better than the CD. The SACD was slightly better than the CD. I've done the same for several recordings. Another example was George Benson - a tribute to Nat King Cole. In this case, the HD download was much better than the Vinyl and slightly better than the CD.
To me, I have found DSD/PCM HD downloads to be the safest. Vinyl is a close second, but I have had to send back a few new records for a replacement due to a bad pressing or whatever. CD has consistently been just mediocre.
At the end of the day, it's all about the original recording and mastering. Many great recordings are being remastered because we have better technology and better understanding of the reproduction of sound. If a recording is poorly done and poorly mastered (Adele, are you listening?), then no format can save it.
I will add this last thought - I have personally found that if the original recording was done on analog tape, staying in the analog domain (vinyl) sounds the best. However, if the original recording was done in the digital domain, then staying in its original sample and bit rate (and not downsampling or converting to analog for vinyl) - sounds the best.
But like Ray mentions above - sometimes, it's just a real crap shoot, leaving one to wonder "who is manning the ship?"