Bitcoin is a good investment now because its price just keeps going up. In fact bitcoin is the best investment in my opinion. The early adapters are lucky to have bought at a very cheap price, but it's still very profitable today compared to other investments.
This trend will continue as long as bitcoin will be having a stable price. But as per the mining estimation, it may require another hundred years to get a stable price. An investment without price appreciations will not be attractive nor good in common sense. So, bitcoin is a good investment now and till it gets a stable prices.