The biggest hurdle for using Xerces as a library has been the lack of support for the GNU toolchain during the build process.
As of the 3.0 release, beta due out in weeks, the standard chain of:
* configure
* make
* make install
will be in place.
The user community is helpful and friendly, and the developer community is active and quick to fix bugs.
One drawback is that because of the long gap to introduce the new build process, the developers have been slow to introduce new features.
This library was converted from the successful Xerces Java library. It is enormous and leaky. Of 18K+ Debian packages, only 3 actual programs use it. You would be well-advised to use libxml2 instead.