@OP: I LOVED the Socratic dialogue! What a lost art form. So here is my response:
Socrates: Young n00b, what is the truest Form of keyboard?
deathsycthehe11: It's the Tenkeyless, is it not?
Socrates: Ah, I asked you for the Form, and you give me the shape?
deathsycthehe11: Well, I guess I didn't understand the question. What the hell is a "Form" anyway?
Socrates: The Form is the perfect embodiment of a thing, while it remains aspatial (transcendent to space) and atemporal (transcendent to time).
deathsycthehe11: wut?
Socrates: Well, what do you think a Form is?
deathsycthehe11: How should I know? And you can't just answer my question with a question.
Socrates: Why not?
deathsycthehe11: Because you're not actually teaching anything, you're just asking ridiculous questions, that are meant to confuse the student and make him feel stupid.
Socrates: Am I?
deathsycthehe11: Stop doing that.
Soctrates: Doing what?
deathsycthehe11: I give up.
Hmm, that Socrates was kind of a douchebag. Anyway, to answer your original question, GET BOTH. Get a Filco and a Leo. You won't be sorry. If you have to choose due to budgetary constraints, then let me compare the Filco and Leo for you. The Filco is like the very sophisticated city-girl that you will meet at a Manhattan cocktail party. She is very chic and very elegant, and reeks of class and money. She's been to all the right schools, and is witty and charming and clever. However, with all that sophistication comes an ability to mask her flaws. And she has one, but it is also part of her strength. In the case of the Filco, it is the metal plate upon which the pcb and key switches are mounted. This metal plate gives the Filco it's strength and heft, but it also creates a vaguely metallic resonance to every keystroke. This to some is a fault, but to me it is a note of quality. Now, on the other hand, you have the Leo, which is like the girl that is fresh from the cornfields of America, like maybe Iowa or Nebraska. She's just recently arrived in Manhattan, and is eager to prove herself in the big city. However, she is a still carrying a little extra weight, and is not wearing the right shoes. She's a little socially awkward, because she doesn't really know what to say or do at a real grown-up party, the kind without a keg of beer in the middle of the room. However, once you start to talk to her, you realize that this girl has a lot of potential, she has everything she needs to be successful, and one day will probably blow everybody away. That is the Leo. Right now, it's a little less sophisticated of a design, and is a little pugdy around the middle. And the fold-down feet are just not great. However, there is no metal plate, which may be a bad or good thing, depending upon how sensitive you are to certain sounds. Overall Leo's are excellent keyboards, they just don't have the polish and sophistication of Filco's, or at least not yet. But you won't go wrong with either one.