here's my versiontracker.com review, which i wanted to share...
I remember checking out oXygen a while ago, and I have to say they made enormous headway in their UI (which is the most important thing for an editor, I believe). it fits in nicely with the system (very unlike those unhappy Java ports that I've come used to see). Colors are meaningful, keyboard shortcuts are OK.
An earlier post criticized that a lot of things were still lacking. Entities are supported with a popup, if you type an ampersand &. Automatic conversion would be better, of course. Drag and drop within the editor or from outside is missing indeed, but what's worse is that a double click holding the mouse button doesn't allow you to extend your selection word by word (it doesn't even select the first word). The tree editor seems to have its occasional quirks, too (not showing attributes despite attribute button selected).
The UI is overall a little sluggish, probably due to the Java foundations. But that's not a big problem any more. The software has been really stable - no crashes, no strange errors. These Romanian programmers did hell of a job!
Overall, after a day of use, I'm keen to buy this baby. 50 US for academic use is not much (with the current exchange rate, yeah!).
Best XML editor on the Mac I've seen so far!
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