The question shouldn't be how safe, but how risky? Risky because even if we have great faith and belief in one currency, it is still unwise to place everything in a single investment. And if this investment fails, there will be no support. Meaning we will have nothing else to draw something out for us to start over. So it is always smarter and wise to expand our investments so if ever one fails, we still have those others to back us up!