I had a small fault on my early 2015 rMBP. I've had a replacement through, but oddly the keyboard feels quite a bit different. I wrote a 5000 word essay in the time that I had the original rMBP so I was fairly well acquainted with the keyboard. This keyboard has a different feel, almost like the keys are firmer, taking more pressure to press, and have a more muted ' sound when being pressed, as oppose to the 'clickier' feel before. I've been using a mid-2010 MBP since it came out so I'm not new to mac. Is this all in my head, or is it possible for there to be discrepancies in the keyboards (however small)? Or do keyboards have a 'break in period' or something I'm not thinking about?