My experience with early Ruby XML parsers is that they were all "how hard can this be?" hacks someone did over a weekend by people who didn't really use XML or understand the ecosystem of specifiations and thereby barely worked and often didn't support fundamental things like namespaces correctly. It took away everything which made XML powerful and left you with something that was often even finicky.
Yeah, I worked on a Rails 1.x app which integrated with an xml feed. IIRC, the options were a library that used regexes internally and had horrible performance (but might have been fine for rss feeds), and another library which wrapped a C library and used callbacks[1]. Definitely was a huge pain point and probably was a mistake for me to use the latest hep environment for that app, but for the rest of Rails it might have been worth it.
