The whole point of the X3 is that it's an affordable hi-res player. If you don't own or plan to buy hi-res files, why on earth would you choose the X3? Just about any portable can play a variety of lossy formats, and many of them can play FLAC or ALAC. Just about any smartphone can, too. There are
so many options available.
I bought the X3 because almost none of these alternatives offer 24/96 or greater playback, and I have a lot of hi-res music. The X3 has a high-quality DAC, a built-in amp, and a quality line-out. For $200.
I have several dozen MP3 files of out-of-print songs, but that's all, and I have lots of ways to play them. I don't care if they don't sound great on the X3--they don't sound great on anything. I wouldn't put them on my X3 in the first place--I need all the storage space for hi-res.
If you have most of your collection in MP3 and didn't rip to lossless in the first place, you made a big mistake, and compounded it by buying a hi-res player to put them on. Ignorance can be expensive, cut your losses and sell your X3 and buy something more appropriate.
I think the philosophy behind FiiO's priority list for future dev work is right on target, and I appreciate them taking a stand for the right way to do things in the face of all the noise on this forum.