Bitcoin can be an asset for now but bitcoin is a currency. Buying currencies for any other purpose than buying goods or services with them is speculating. Furthermore with Bitcoin, it's impossible to work out how to assign any value to them. You can get an idea of the real value to you of a physical currency by looking at what it can buy you with it in its country of origin (compared to what you can buy elsewhere with other currencies), interest rates in that country, inflation, and how rapidly the currency base is expanding compared to economic growth. With Bitcoin, how its value should be measured is anyone's guess.