Gammajo, Playing on my system as I type - Rachmaninov's Preludes by Rustem Hayroudinoff on Chandos. Not a Bosendorffer Imperial I think but this is one of the best recorded and well played disc's I have if I'm up for Rach's complete preludes. Rich tonal quality w/ a warm deep bass.
Back to the Bosendorfer - something unique - Telarc created 2 CD's using Rachmaninoff's piano rolls played back electronically thru a Bosendorfer. Don't be put off by the process - unless you are an expert you wouldn't know there wasn't an actual pianist at the keyboard. One CD is Rachmaninoff playing his own works "Window in Time", Vol 1, and the next is Rachmaninoff playing works of other composers, Window in Time, Vol 2. Excellent reproductions of the piano's sound. As with the Hayaroudinoff these should be readily available.
Enjoy them, I do!