I have to disagree about the constant tweaking thing. I thought that too before I owned one. Once set up properly, it should maintain it's alignment for years and it shouldn't need anything until you change the cartridge. Even then, it's probably only a matter of minor adjustments. But I do agree you need a very good setup person.
Of course, if you're the kind of person that will live in the state of constant grief, worrying that the table needs tweaking, you're probably better off with a different table.