Just to address custom built computers, I dislike 'em just because I can't custom build a laptop

(or if I did, it would be hacky and bulky).
Beyond that, with a little time it is no hard job to find a computer with the spec I want that has the perfect visual design-- when I do the actual research I don't compromise just because someone else builds it. And its often the surprise of additional features that I didn't realize it had. For instance, I didn't realize my computer had an SD card slot, and only realized exactly what LightScribe was after I bought it which was awesome too.