how to choose road bike?

[DavG]

Hi! When I came to this forum, I was fascinated by the idea of buying a new marathon bike. I know it's okay to have two or more bikes. I have a mountain bike and want to upgrade my old one. Here I am deciding between two options https://gym-expert.com/best-road-bike/, which seems to be the best? I like SAVADECK, even if it costs quite a lot. But I also like 6KU. Just wondering what will be best for the marathon.