The fat PS3 is the best, it looked expensive and cool. I like the PSOne model and the Dreamcast too. PS4 looks good too as the last Genesis model and the Wii did.
For handhelds, I think the Vita and the PSP looked great with that black piano finish.
For each company, I would say Sony did its best with the fat PS3, Nintendo with the Wii and MS with the X1 (I think it's too big, but it has a nice discrete design that I enjoy).