My friend two Sengso clocks and gave one to me the day before a comp. It took me awhile to figure it out, but it was a fun challenge. When I decided to go for speed, I ordered this puzzle - what all the cubers I know call "the only real option" in terms of best clock. I understand this to be what most or all of the pro clock solvers use and I can understand why - the dials move smoothly, the arrows align magnetically, and the points are clearly marked for easy recognition. All that plus the awesome shade of green render a 5/5 star review in my book.