I have experienced plenty of players out there that think they know they won't like some game or another based on what (very little, in most cases) they "know" about the game... never actually Shadowrun though.
Despite me not meeting anyone not into the cyberpunk/fantasy cross-over... which I have to take an aside about here: What we now call "fantasy" originates in the same fictional works as what we now call "science fiction", and the only difference between the two is the degree to which the fantastical has been explained. For example, a terrible winged beast with a man-like face, cruel intelligence, and a tail capable of flinging sharp barbs at quite a distance is either explained as being some species of beast native to a "non-earth" world or another dimension and it is "sci-fi", but if you say "yeah, it's a manticore just like in myth" then all of a sudden it is "fantasy."
"fantasy" is "sci-fi" in which most people don't know the answers to the questions of the world, and "sci-fi" is just "fantasy" in which a lot of the mysteries have already been investigated, researched, and solved.
...anyway, back on track:
When a person has preconceptions about a game that I like and would like to run for them, I just have them talk about them with me - and it is as simple as saying "I'd like to understand why you apprehensive about giving this game a try," and listening to their reasons. The key is to offer solutions to any solvable problems, and correct any misinformation they might have received, without being too pushy or making it sound like you think their opinion is stupid.
All the players I have ever met (rough count being about 180) have had some game(s) that they don't like for one reason or another, and in all but 2 cases I have managed to get them to at least try that game out again (because every game is different from GM to GM) - the 2 cases both actual regard Vampire: the Requiem: 1 guy refused to play it because he was hard-core into Vampire: the Masquerade and was just plain not going to try out any other Vampire game no matter what I said, and the 2nd guy had an extremely terrible experience with Vampire games before he ever met me and is afraid of any unenjoyable situation to the point that he and I once had a minor disagreement and he immediately left my house and I didn't see him for 2 years.... so I am pretty sure you'll have a good chance of getting anyone to try Shadowrun if you ask them to give it a shot after understanding what they don't think they'll like about it.