So far, I'm very, very happy with the machine. Coming from a mid-2009 C2D MBP 17" (a real champ, but I couldn't afford to wait on upgrading anymore...) the maxed-out 15" blew my mind.
Positives: amazing build quality, best screen and best speakers ever seen on a laptop, great trackpad and keyboard (many don't like it, but I do), blazing-fast CPU and GPU, insane SSD drive. I initially had some problems with the Radeon 460 kicking in, but I discovered this was due to a couple of specific apps and closing them did the trick. Battery life is good enough, I get around 8h with light use (but I keep a lot of apps open all the time).
So-so: haven't found the TB commands really useful so far, as I'm generally quicker if I perform the same operations without taking my eyes off the screen. Also, I agree it's too sensitive, it's easy to trigger buttons by mistake, some sort of force touch would have been welcome. Using dongles all the time sucks but the move to USB-C was a right one, it's a superior standard and the industry needs to be pushed towards widespread adoption.
Negatives: a computer selling (in my country) for a whopping 5000€ should really have offered a 32GB RAM option for heavy-duty users (people who do number-crunching on very large data, work on huge video projects, run several VMs, etc.), even at the cost of some battery life. Sure, it's a fringe requirement for a minority of users who might want to use a behemoth-level desktop anyway, but hey, I can't carry my office workstation on a trip or use it on my couch
Overall considerations on my purchase: I had the opportunity to buy the MBP using money from a professional budget, so I just splurged on all the upgrades because why not? I can't possibly regret the purchase, it's the fastest, most beautiful and most powerful laptop I've ever used. Had it been out of my own pocket, though, I would have pulled the trigger on the base 15" + 1TB disk upgrade, the higher specs are great but the 1500€ price difference is staggering...
