X3 vs Miniplayer A/B testing. Unsurprisingly, the winner is X3.
I guess some people (not those who have been using a portable amp) do concern about the portability of X3.
But considering that X3 has the coaxical out, line out, TF card slot, and most importantly a powerful amp, I think this size and weight are justifiable.
But it's always better to be thinner and lighter for a portable gadget.