The MGC 4x4 is just such a great cube. I got the speed micro-actuator version when it was on sale for a very good price! Some of the reviews said it was a bit sandy out of the box, and I thought that meant it felt rough to touch. I was absolutely wrong! It is so smooth, very grippy and I didn't even get the UV or PVC coated versions. (As shown in the picture below). I understood what it meant when I started turning, it felt a tiny bit like some sand had gotten in (it of course didn't have any sand in it, it was just the feeling), and now after a few days of having it, the feeling has gone and I have cut my time by about 40 seconds consistently! And the first time I solved it, I broke my record straight away; I was so happy!
The MGC 4x4 is amazing. If you are looking for a cube that is not too expensive but has great magnets and is very fast-turning, I would absolutely recommend this cube.