Depends on how one defines "best". An MA tells the trader nothing about whether or not price is trending; it tells the trader whether or not price has been trending. And that makes a great deal of difference with regard to what the trader is to do next. And trading is all about what the trader is to do next.
MAs follow price movement. The price trader does the same thing. But the price trader -- generally -- has a brain. The MA does not. Therefore the price trader can reach a decision based on what price is doing in real time, not guess based on what price has done.
"Best" has to be derived from the trader's individual strategy. So there can't be one "best" MA for everyone at any given time, though they may all say they are trend-following this same market. Of course, "best" cannot simply be measured by something universal, like % gain per day for example.
But trends tend to continue, that's the most probably next movement of a price in a trend, that's why tends exist as a pattern and why they can be recognised. So I have to think that the most consistent trends are the most likely trends to continue. And that is really what "best" means to me, but that's just me. MAS's are a great tool for recognising and quantifying multiple characteristics of trending prices.
At the end of a day, buying a market in an uptrend isn't guesswork.