In Russia there is lot of different kinds of public transport. Bus is the cheapest public transport. That is why bus is one of the most popular public transport in Russia.
I think that taxi is more comfortable transport than bus. That is why I prefer taxi.
But if you want to travel the best option for you is the train. Train is not so comfortable and fast as plane but it is cheaper. Busy people prefer plane because they haven’t got free time. But the plane can be delayed and you will be late for a conversation.
So I prefer plane and taxi because they are faster and more comfortable and I can afford it because I think that price is not the main.