"Most respondents commented that although newspapers or magazines were more reliable than *hardly any* the electronic sources, in fact *any* of the three, TV, radio and the Internet, was more convenient"
This is the only sentence I have an issue with.
"Hardly any" means "very few". If you say that A is more reliable than hardly any of B, then you're saying that B is usually more reliable than A.
"Any of the three, TV, radio and the internet" - This isn't correct as it is. You could put "TV, radio and the internet" in brackets. You could also just say "Any of the three" (if it's known what the three are) or "any of the TV, radio or the internet".
Here's how I'd write it:
"Most respondents commented that although newspapers or magazines were more reliable than most electronic sources, in fact any of the three electronic sources (TV, radio and the Internet) were more convenient."
By the way, you misspelled 'healthy' as 'healty'.