I've tried Dell and HP, but now I'm using Lenovo.
So far I can say that I am most satisfied with my Lenovo.
I've got great specs, it's lightweight (as compared to other big laptop brands) and the price is right!
I haven't tried Dell yet but I have chance to use my cousin's lenovo laptop but when I used it, it has already some missing keys.
I guess that was because of the user and not the brand itself, although I am using HP that was given to me as a gift. And I'm satisfied even though the specs is not too high.
But still I'm convenient using it with my programming projects.