This Rubik's cube was my first Rubik's cube that I got in 2007, back when I wasn't a speed cuber. At first, it was very, very stiff. I lubed it with Vaseline 3 months ago, which wasn't good for your cube. About 2 weeks later, I cleaned it out and put in silicone. Because of the Vaseline, it isn't speed cuber quality. Also, some of the stickers started losing color because of peeling the clear outer layers on the stickers. Later, I got two "Dian Shengs", which I'll talk about later. They came very smooth, so I didn't lubricate it.
EDIT: I actually later did lube my Dianshengs and they are even better.