Buy the Mf3rs2. The thunderclap was my first cube and it needs cleaning and lubing very often. After some days, after i bought it and did nothing to tune it, it slowed down extremely. It also got a weird touch / feel, as if my fingers would be glued. Got to clean it, and, lubed it the first time. It then got it's speed back, but now it got it's slowlyness and bad feeling back. I don't like the cube anymore, but it's now at "Work", so i don't care about how it's used anymore. The Mf3rs is definitely better, the Mf3rs2 is also very good and the yuxin little magic would be my recommendation.
