What's nature and magnitude of the difference in sound quality between Foobar using the Secret Rabbit at 24/96 vs iTunes at 16/44 on a PC based platform?
I believe iTunes does not bypass Windows KMIXER, so it will never sound better on a PC. Great on MAC though, although many customers have reported that the MAC upsampling is not so good.
The difference is in the smoothness of vocals, imaging and detail.