libcxx support library

I would like to install clang 3.3 with libc++ on Linux where g++4.4 is
currently the default/only toolchain. I'm not sure how to choose the
best support library: libsupc++/libc++abi/libcxxrt.

Concerning libsupc++, I noticed this:
Are there other issues with using libsupc++? Doesn't it even make sense
to use libsupc++ 4.4 with libc++ when I need C++11 support? What would
be the limitations using it C++11 if any?

Which of these support libraries would be the most mature? I care most
about stability and standards-conformance. Interoperability with g++ is
not important.