Yeah it was sort of the same with mine. I ordered the 256/16GB model and then I started to read lots and lots of really bad comments. UI lag, scroll lag, screen ghosting, long boot times, and whatnot. I received mine a week ago and I was hoping for the worst. Surprise, no lag, no issues, this is actually by far the very best computer I've ever owned, or used for that matter. I am pretty objective when it comes to computers. I study Computer Science here in Mexico and I've been obsessed with UNIX systems for a while, that's why I made the change to Mac I hated Windows. I have ML as the main OS with Ubuntu running on Oracle's Virtual Box and I partitioned the drive and run Backtrack natively. My computer runs perfectly. Very fast system, flawless screen. I am really happy with my purchase and Mountain Lion is a really neat OS. The retina MBP is just as good as it gets right now.
Hi I am also from Mexico, and I bought my retina like 3 months ago and so far the only "issue" that I've had was that I unplugged a usb receiver for a microsoft wireless mouse and immediately the machine crashed and rebooted, but has only happened once, and I use it on a daily basis and for many hours so it's the best computer I have ever had.
I have a question though have you tried to install backtrack on virtual box and if so, have you been able to put the wireless network card in promiscuous mode inside the vm? or is it necessary to install backtrack natively