The first comic I actively remember buying was Conan(The Dark Horse version). I had been introduced to the character when I was maybe 9 years old by one of my uncles. I was a veracious reader and he had gifted me a copy of Conan the Conqueror. It was a rabbit hole for me that I happily fell into.
After reading through a number of the books I was introduced to the movies. Conan had such a HUGH affect on me and is pretty much the bar I use to grade all fantasy. It MIGHT also be why I love playing a barbarian in a lot of the video games I enjoy.
He has an honor about him and a loyalty that tickled my brain. He has a way of collecting certain sort of person. The comics told so many complete stories. There was fantasy creatures - but not so fantastical that you couldn't believe they might actually exist.
Of course there have been dozens of artists for Conan - I think Yeates and Buscema were 2 of my favorites. NOT to say Boris Vallejo wasn't amazing. If memory serves I don't think he actually did a comic, more like posters and paintings.
I don't currently have a preference to Dark Horse or Marvel - but I haven't gotten a comic in a long time. Last time I picked one up I wasn't to thrilled with the art work or the story. They seemed very bland and flat to me.