Using locales comes with their own set of pain, and throws you at the mercy of whatever is installed on your system.

I've no idea why you would want to use locale to do XML stuff with - AFAIK, XML implies Unicode. And if you're doing Unicode, you shouldn't do locales.

As for your second question, AFAIK, Maketext and locale do different things. I don't see how one would replace the one with the other.