• Not easy to learn, moves many more keys
• Doesn't retain ZXCV in their QWERTY places
• Keeps the semicolon in the home position.
• Colemak has the Backspace on the home row, which makes it easier and faster to correct errors.
• X-fu has 15% more finger distance
• X-fu has 150% more same-finger typing than Colemak
• X-fu has 100% more same-hand row jumping
• X-fu doesn't take into account hand balance and finger balance. The right hand is overworked, and the right index and ring finger are overloaded.
• X-fu is a work in progress. Colemak's design is considered stable.

Single sentence description:
X-Fu layout has been generated to minimize typing effort of English text using an effort model which includes effort contribution from stroke path.

Full description:
The X-Fu layout is a keyboard layout which makes typing English text much easier than QWERTY (not hard), Dvorak (not hard), as well as Capwell and Colemak (harder) see full comparison. The layout was generated using simulated annealing and a typing effort model which attempts to quantify the notion of hand and finger strain during typing. The model describes effort using

• individual key location weights (e.g. keys assigned to the pinky require more effort)
• long-range correlation in effort in which previous key strokes are used to weight the effort of successive ones
• stroke path, composed of components that monitor hand, row and finger motion to maximize the number of successive key strokes that are more comfortable (e.g. those with hand-alternation [afa], monotonic row progression [tab vs bta], monotonic finger progression [wer vs erw], and so on)

The X-Fu layout is generated by starting with the QWERTY layout and relocating only the character keys. Unlike Dvorak and other layouts see layout table, X-Fu has all its punctuation in the same location as QWERTY.

I am working on other layouts in which punctuation is remapped.