If you're questioning weather or not to return it I think ultimately you will so just get it packed up and sent off. IMO you'll always find a little imperfection on anything. Across my filcos they've had creaky keys, wobbly stabilisers here and there. Also noticed a couple of the keys on my filco ninja brown have sort of slightly grindy springs after the tactile bump. I only noticed the one on my "A" key because in FPS games sometimes I slowly press.
I always go looking for imperfections though and on everything of course I find it, I really should stop 
. This sounds like more of a defect though, anything you'd actually notice while in game or during a typing flow isnt good.
I 100% understand you...im exactly the same way, always overanalyzing all the time.
But this is not an example of that..
My filco ninja also has squeaky keys, especially backspace, and truth be told...it had scratches along its sides from when they were putting it into it's box in the factory (just like the das keyboards did, but 99% unnoticable because of the different plastic). Mine also has wobbly stabilizers...but the cherry mx keys are supposed to be wobbly...thats how they work the way they do from any angle. You can hit it at a 15 degree angle pushing foward and it will work perfect. I don't care about any of these shortcomings because the keyboard looks great, and all the keys type amazing, except for the f7.
That is my problem here...that the f7 key is messed up so that i cant press it pushing a little forward and feel the same linear switch that i feel pressing that same f7 pulling backwards.
Try to take off the key caps and put your finger on the + now, try to wiggle it around. Youll see that they all have wiggle, and its on purpose.
I'm def going to replace this board...but amazon is being lame, and their return center on the site isnt letting me give a reason for the return...thus i cannot return the keyboard right now. But its cool, i have till july 27th.
