On the question of #8 vs A3 plugs and which nitro content for beginners, I would personally suggest ammending the article to say that those choices should be based on the manufacturer's recommendations for the particular engine. If we're talking about an engine that's made for low or no nitro like a Super Tigre then it's a good recommendation to stick with that (or at least it's ok to in places where nitro is expensive). But if we're talking about an O.S. or any other engine made for the American market, starting out with 10% is the best. Same with plugs- the manufacturer designs the engine to run with a certain one, and changing it makes tuning harder.