I have owned 10+ pairs of the La Sportiva Katana’s – basically they fit my feet better than any other climbing shoe I have ever had. I have pretty long narrow feet with ‘big’ big toes, and the Sportiva boots seem to fit the shape of foot pretty well; for me a boot that fits is the most import aspect of any climbing shoe. The Katana’s are reasonable technical boots, but are comfy with the velcro closure and large tabs they are easy to synch tighter for harder pitches then slacken off for easy pitches or undo on belays.
I have used more technical climbing shoes in the past which I could only keep on for about 5 minutes at a time, which meant they were useless for anything other than bouldering; I would be unable to stand on anything by the top of pitches due to my toes hurting too much. The Katana’s are a good compromise between technicality and comfort – I can wear mine all day on long routes as well as do hard moves requiring delicate footwork in them (the rock boot is not the limiting factor my foot work is). Hence I use my Katana’s on everything from alpine rock to sport climbing.
The sole on the Katana’s is really good – hard-wearing and sticky, and the new XS Grip rubber is stickier than the old version vibram. I find the Katana are excellent for smearing and when newish work well on edges too; however once they have become quite worn I find they do loose there stiffness at the toe making them poor at edging. So if you are planning on climbing lots of ‘edgy’ routes e.g. slate routes, then I would not recommend the Katana’s – however for virtually anything else they’re great.