The backspace key is fine. Really nice actually.
Right shift certainly still works, and is not difficult to access. I use it all the time.
Control location is excellent. I don't agree with the opinion of hjkl_over_wasd, but perhaps we're using different applications.
The \| and `~ keys are arguably the most difficult keys on the HHKB layout. I use these keys a lot. They're essential for programming in a language like c, ruby, shell and many others. 75% of the time I had to look at the keyboard to hit the key. The other 25% I hit adjacent keys by accident and got pissed off. There's also something weird about the spacing of the symbolic keys on the right side of the keyboard like [{ and ]}. I missed those a lot too, and I'm not really sure why, but they're also critical to programming and again, pissed me off when I didn't hit them.
Anyway, after a couple of months or so I'd grown quite acclimated to it and didn't have problems, but anyone that has been writing code on ANSI for several years and is buying the HHKB to do some real work with, needs to see this disclaimer. The HHKB has a learning curve. It will take you some time to learn its layout. For all my efforts, I still refuse to let it leave my possession in exchange for naught but a charlatan of a kb. Let that be an indicator to you all of how awesome this keyboard is.
But do not despair, young hobbit. By virtue of patience, you will reap great rewards in the quality and joy of your work. The HHKB is without a doubt, the best keyboard I've had the pleasure of journeying with through everyday life. I'm glad to have it with me, here at the end of my post and this thread.