Ketchup probably works due to its vinegar content.
It may seem a minefield but apart from avoiding the hideous mistakes, you'll be choosing between something that's good and something that's either as good in different ways or 99.9% as good - ie. you're gonna be fine with either.
The ZMT may well be fine but it might be a case if trying different fittings to see what gives enough grip. If you're after a slow build with plenty of spare time and budget, that's fine and you'll probably have some useful feedback for others afterwards...plus some colourful new vocabulary and maybe a little less sanity. But if you are short on time/money/patience you might want to steer clear of the norprene based stuff unless someone can state exactly what works well with it from experience.