- The build quality will not be like what you are used to. The entire chassic will flex and the keyboard will feel more like a trampoline than the keyboard on your Mac.
- Customer support will be useless, just write that off now.
- Keyboard layout might be a little bizarre, I have not looked at this one. [Ed: just looked, wow thats bizarre. Tiny keys, weird arrows, num pad is strange. Just take a good look before you pull the trigger. Not saying its bad, just ... odd. OK maybe bad.]
- Webcam will probably be worse than you are used to
- Trackpad will be light years behind your Mac both in feel and how it performs. Apple just has this figured out and no one else can touch it. Might still be "good" just wont be "Apple good".
- Quality control will be really poor compared to Apple, you might have dead pixels in the display or other build quality or QA issues.
- Prepare to spend the first 15 minutes peeling off stickers and the glue from them.
- You will probably want to just wipe it and re-install Windows or install Linux vs "de-crapwaring" it. No idea what Linux support will be like and I would be hesitant to be the first one to buy one to find out. And this is from someone who runs Linux exclusively.
I loved both of my 17" MacBook Pros (2003 and 2007, both of which still work). But Apple doesn't care about big screens and proper keyboards anymore, so this is very attractive to me.