I have used Orca, and I can't stand it. The main advantage is a global place to route text for speech synthesis, but I simply hate using screenreaders to use applications which are not designed with accessibility in mind. There are few better solutions for browsing the web, though. I've been meaning to try lynx with brltty.
> I simply hate using screenreaders to use applications which are not designed with accessibility in mind.
I can understand that. I think many of us have just accepted that it has to be this way, because we're a minority and we want to have all of the advantages of using mainstream applications (economies of scale, active development, not being at an extra disadvantage compared to sighted peers, etc.).
Of course, you don't fit the profile of a "mainstream consumer" when it comes to computers. In particular, I gather that you take full advantage of the hackability of free software. So using custom TTS plugins as opposed to a clunky generic screen reader is just an extension of that overall approach to using computers.
If Orca is the only GUI screen reader you have tried, I can understand you being put off. Try NVDA on Windows with Firefox and you'll never look back. NVDA is open source btw.