That's not even close to true. Just because you are and one person isn't or hasn't yet is no where near enough to be sure whether your experiencing a software or hardware problem.
It could easily be 3rd party software not ready for Mavericks. You need to do some real troubleshooting. The Kernel Panic message tells you what caused it. Console logs and activity monitor also help trouble shooting when fans spin up what else is running, using high cpu. How many photos are you importing, from where. etc etc. So many variables it's certainly not as clean cut as you're making out.
I suspect part of the problem is your unfamiliarity with the OS. IE You couldn't figure out how to right click trash items a few days ago etc.
But look if you're having buyers remorse (you have 14 days to return) then just return it. Otherwise do some troubleshooting.
You are right about me being unfamiliar with the OS, that was actually one of the reasons for me buying it. It's new and fresh, and exciting. I really didn't want yet another PC. Definitely not buyers remorse, but yes, after spending over £2,000 I don't want to be left with a lemon (IF, that's what it is).
However, many of the issues I had with right-clicking wasn't down to user error. It resolved itself after a reboot. Maybe just one of those things. I'll keep my eye on it.
The fans are quite random. I wouldn't call importing a few photos (approx 300) from a USB3 external HDD to the internal SDD to be taxing. They don't always do it. That's the issue. I can be sat on the desktop and they will spin up like crazy. I've not got that much software installed, it's pretty much just Mavericks installed, iPhoto, iMovies, iWorks.
Sounds to me like it 'could' be a driver issue with the 750M (seems to be quite common on the mac forums. I wouldn't like to think 3rd party software could cause the OS to kernel panic and reboot. Mavericks should at least have a kernel on par with Windows. Yes, software crashes, but it shouldn't take the OS down with it. This is why I'm thinking it's down to a buggy driver.
If all else fails and it is hardware, I think I have 30 days to return. Like I say, really love the laptop, I'm getting on well with it so I don't want to send it back if I can help it.