Yes for Six Flags, No for Disney. As much as I admire Disney (though not very fond of magic), Six Flags has superior rides. I will always remember the Great American Scream Machine they used to have. Fast speeds, come on! Who can resist that? Lol Icon of greatness. Also, the best part is that it's within a relatively small distance of New York City or any farm or town near the park. Granted, Universal is also good, better than Disney also.
Six Flags is the kind of theme park that I would want go to. Especially Six Flags Magic Mountain. Six Flags has the scariest roller coaster in the world. There are few Six Flags that I would want to go in America. Six Flags Magic Mountain being top of the list.
Disney Land is for children, with childish attractions!!
If your in it for the overall experience- go disney. Though Six Flags wins in the Thrill cateogry, Disneyland is more of the theme parks with fun immersive rides and set designs. They have cooler technology and shows and overall staff at Disney. Six flags if you want Coasters. Go disney if you want to ride through a temple, go on a boat ride with pirates, fly through space, go on a star wars space flight, watch a parade, see fireworks, see theatrical plays, go intoa 5 star restaurant. Disneyland wins at the experience.