I dig it. They are useful, but that can't be done with "standard components".
The whole idea of a flexible and upgradeable PC is kind of against the Apple "tightly coupled" software and hardware story. The reason that their user experience has historically (I haven't used a mac in about a decade) been so good was because they limit the available hardware for their testing purposes. They don't have a lot of choice in hardware, but what they do support works every time.
I don't know...I got off the Apple train a long time ago. I loved my Mac Pro, but it just wasn't for me.