Well, it depends. If what you need is just a fast-and-easy-folding commuting bike to take you from home to subway station, then a Brompton will do that perfectly.But in your case, weight and speed mean more, so it is obviously not very attractive to you.
Some say, if you are a folding bike enthusiast, sooner or later, the Brompton is the way which must be passed, no matter it ends up with you hate it or love it.