Aluminium space bar - Tp4 - really!
Try removing the space bar and placing it on a completely flat surface.
See if it sits flat or whether one end is higher.
This is a common problem with space bars, especially PBT space bars. Although I believe this one is ABS, however it is still a possibility.
Post a pic if you can ![Smiley :)](https://cdn.geekhack.org/Smileys/solosmileys/smiley.gif)
http://i.imgur.com/YvTG4S8.jpg
http://i.imgur.com/fYtvqv0.jpg
http://i.imgur.com/X5g7i7W.jpg
It does seem a bit warped..
I have a spacebar from my cm quickfire keyboard that i used to test if it was a spacebar problem. it still feels a little bit sluggish. i'll post a video of it later..
would it be that the cherry stabilizers are less tolerant to space bar deformities?
That is warped, although I have seen worse. Cherry stabilisers are sensitive to keycap shape, and especially for the longer keycaps such warping can cause the issues you are experiencing.
As ynrozturk suggested - can you try a different (non-warped) space bar?
If a different straight space bar works, you could try contacting the vendor to see if they can provide you with a non-warped space bar, especially if the keyboard is still under warranty, which I'm guessing it would be.
Or you can try heating the space bar with a hair dryer, or in very hot water, placing it on a very flat surface, and weighing it down with a book or so to keep it flat. However if something goes wrong with this process the vendor might not accept the keyboard back as a return.