It would be GREAT if you can buy electronic sheet music. I sing in two choirs and I carry large music portfolios to each rehearsal. It would be totally convenient if this service was available. With my sheet music in electronic format, I could enlarge sections that I'm practicing, I can easily skip around the pages. I can take maestro notes during rehearsal and maybe even use the iPad during the performance?
The ideal would be to record a rehearsal and then on my own time, sing along with the recording, learning the literature, and being able to perform fully prepared.