1:Have you purchased 24bit music in the past?
If SACD is 24 bit, yes. Otherwise no.
2:If so, what are the sources you have purchased from?
I buy vinyl, CD's, and SACD's, many from Mobile Fidelity.
3:Are you willing to pay more for higher quality audio?
Yes, as my wife has attested in court documents.
4:When purchasing music online, do you prefer a subscription or a pay per track/album model?
I rarely purchase music online, but when I do I purchase the full album.