Steve, the thread here that you linked to, in which a person complains about maintenance, was complaining about the first-generation Gates sprocket. Like the normal chain sprocket for Rohloff, that used to be threaded and a pain to get off. But now Gates, like Rohloff, has switched to a splined carrier for its sprockets.
The Thorn brochure's notes on the Gates drive is also several years old.
I have met enough satisfied Gates users on long tours now, and read very positive reports from others like Alee Denham, to feel that the tech is now mature. I am planning to switch this year myself.
I do not recommend a Hebie Chainglider. I had one for a few thousand kilometers, but it failed to keep the chain clean in dusty terrain and constantly required tweaking for smooth and noiseless operation. I eventually ended up ripping the Chainglider off my bike in frustration at a Peru truck stop and throwing it away.
A Hebie Chainglider also won't give you anywhere near the mileage of a belt. Chains wear out not because of contamination but stretching.