I don't think that it will be right to question the bitcoins comparing to bubble and that too when this type of question is already been asked many times prior. Anyways being a member, it's our duty to answer the queries in the correct way. I personally believed that bitcoin is not a bubble and it is a strong investing asset similar to stocks and bonds which has a strong value and interest which is rising among the people with the increase in demand. It is obviously safe to invest in bitcoin if you choose the good exchange like Binance, Bittrex, and Coinbase and by following the safety precautions.