I think this just depends on the make and model. I did a bit of homework before purchase a few years ago (to ensure good compatibility with GNU/Linux), and my Dell Inspiron N7010 has been serving me faithfully for years. No major wifi issues, no battery life issues.
Similarly, I did some research before I bought my Dell Latitude E4310, and it works flawlessly with Ubuntu, and always has.* Graphics (both on screen and on external monitors), WiFi, sound, even Bluetooth.
It's not a guarantee, of course, but my general impression is that going with "pure Intel" (CPU, GPU, sound, WiFi) laptop helps ensure compatibility.
*It's possible that the battery life is worse than Windows; I wouldn't know, because I've never used Windows on it.
