Xubuntu. Ubuntu because most of the time, I just want a plug and play experience with a huge community. And XFCE because it’s lightweight and has all the tiling features I like.
I really enjoyed tinkering Arch, I learned a lot of stuff, but it’s too much effort for my usual laziness.
Yeah, you’re right, it doesn’t make sense to say that O(f(n)) is good or bad for any algorithm. It must be compared to the complexity of other algorithms which solve the same problem in the same conditions.