It's all about fit - I was once asked by a startup climbing shoe company to provide some requirements, it was quite simple, sticky rubber, no liner so that the shoe could stretch to fit your foot over time with no dead spaces, and no pinching or uncomfortable tightness. That's what these 5.10 slippers do very well. They are also very sensitive, so much so that board lasted or stiffer shoes feel like wooden plans when you put them on and are very disconcerting to climb in.

If these slippers fit you then use them, they are a great shoe, with still, in my opinion, the stickiest rubber available. if you look after them and get them resoled before the rand wears through they might even stand a couple of resoles. My only criticism is that 5.10 don't make the most durable shoes.

They work best on smears, slopes and thin cracks, but I've also climbed some thin edging routes (5.11) too, thanks to their sensitivity. I would venture to say that these are the definitive slipper.