Whether you anti up the $24 or not, I don't believe Joe has put any restrictions to using anything on the Tutorial site. The Charter Member Subscription is to help offset some of his out-of-pocket expenses for acquiring and maintaining the site and mailing list.
But rather than just ask for a donation, in true Joe Waters fashion, he has compiled over 6500 files from the site onto a CD which will be sent to each Charter Member as a bonus. As I understand it, everything on the CD is available on the Tutorial site. Call it a gift, bonus or added value for your charter membership. The bottom line is the $24 just helps Joe offset expenses for providing one remarkable site that benefits all of us interested in the PSR 2000, 2100 and Tyros.
Perhaps no one has benefited more than Yamaha. I hope he gets a check from them.
Thanks Joe.
Eddie