HD Tracks is once only. So back it up. I keep (at least) two backups on external hard drives. A 3TB drive is under $150 now, no reason not to back up at least once.
Going from 16 bits to 24 bits is a huge step up in resolution. While higher sampling rate is ideal, 24 bit resolution has in my experience so much over redbook it is worth the price alone.
I agree in theory, but practice has shown me that any number of 24 bit downloads on HDTracks are, in some cases, not as good as Redbook. In recent issues of TAS, several respected reviewers agree and have discouraged certain downloads.
It's ALL in the mastering and transfer process. I'd rather listen to well-mastered Redbook than poorly mastered 192/24 any day of the week. Some hi-Rez is great....but far too much of what is being sold simply isn't. HdTracks ought to have a quality standard, but they've chosen be a mere vendor. Caveat emptor. Those involved in hi-res sales better address this more assertively or hi-res will go the way of the SACD.
Again, I wish someone with money to burn would compare and post here.
