both are great investments. bitcoin started it all, ethereum has much better technology. but for me bitcoin is a better investment. bitcoin shows a good resistance. Whenever it falls, it comes back strongly.
I think that is because of the supporters or the users of Bitcoin. There is a lot of people that is using Bitcoin. There are a lot of buyers and sellers and Bitcoin is mostly used everyday by some people since they can receive Bitcoin as as rewards or as a payment on the Signature Campaigns you can see here in the forum.