The weak point is surprisingly battery life which nonetheless is still useful enough and enough for many people. The performance although less than the SP3, is still not far off it.
I think Lenovo were more interested in making it as anorexic as it could. I think if you want anorexia though and long battery life they should have dropped the screen resolution to something more sensible. The resolution of the screen is ridiculous and sucks both battery life and performance without giving much back in return.