If the rumours turn out to be true and Apple does release an iPhone 6 Mini I’ll likely buy it.
I got my iPhone 6 at the start of November and switched to it from my iPhone 5s. But two weeks later I switched back to my 5s. Just this week I’m having another go at trying the 6, but I’m probably going back to the 5s again next week.
The main reason is the form factor. Everything about the 6 is better in terms of quality and functionality (camera, screen resolution, speed) but the form factor (ie bigger size) just isn’t as enjoyable for me as the 5s. I struggle with the 6, and I’m a guy with reasonably big hands. I really enjoy holding my 5s (yes, this post comes back to haunt me). It sits well in my hand, doesn’t slip, and is easy to use.
If the iPhone 6 Mini is exactly like the 6 in all other regards, but just with a smaller screen, then I’m sold.