At an average of 1:15 you can definitely have to work on your solving, like fluid turning, look ahead etc. You should however upgrade from a store bought Rubik's brand cube because those really make solving not enjoyable at all. Guhong or Zanchi? Each cube has a different feeling. Guhong is smoother but has more resistance in turning and Zanchi is a lot faster and lighter to turn. Honestly, I would suggest getting a Guhong because is much more smoother making it more controllable. The Zanchi is too light and fast which makes it hard to control leading it to over shooting causing little lock ups. Guhong is an excellent beginners cube. Sentence and link removed. If you're going to plug your cube site in your signature, please do not do it in the post as well.
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