Just getting into the hobby and JL has helped me through some growing pains.
When I first started I dropped by to pick up test kits, John suggested that I go for Salifert tests. Thought to myself, "I don't need that fancy stuff", cheaped out and got API against his recommendation. Well long story short I now have the "fancy" Salifert kits. Lesson learned, listen to John (although I wouldn't admit it to his face

)
I'm lucky to have them close by.