Not that anyone should particularly care, but since I've had a rather chaotic slew of cameras since around 2007 and have been particularly interested (and invested) in Samsung gear in recent years, I figured I'd chime in with my 2,000 Yuan on this currently-latest model.
Please excuse the Wall of Text, I'm using 'big paragraph' mode.
What impressed me most about the NX100 was its basement bargain price and IQ far better than some critics and forum types would have had us believe. In fact, some of my best shots were with my NX100, and I was quite happy with it after I got over my fear of the 'awful styling' (which wound up being very cool and comfortable with a Horus Bennu case). I found a few neat old Konica Hexanon lenses and got an adapter, further enhancing the flexibility and fun with MF vintage glass. JPEG processing at higher ISO was terrible, though, and the operating speed was mediocre. The hard plastic build (there are grades of plastic, to be sure, but this was slippery and felt a bit cheap) was to be expected for the price, but still not ideal. Controls and ergonomics were really nice, though - control wheel and top wheel plus iFn made for more EV adjustments on the fly than I could use without growing more fingers. No DSLR I've ever used was easier to do quick on the fly fine tuning in M mode. Opted for the 20-50, which at the time seemed the IQ champ compared to the OIS 18-55.
When the NX200 dropped to a low mark after the NX210 was announced, I made the jump and my concerns about 20.3MP high ISO noise were laid to rest. Chroma performance was very easily mitigated in LR with the slightest bump of the NR slider, and I still say the 20.3 is one of the best imaging sensors available, even today. Razor sharp, lovely evocative tones and the shadow range just goes on forever, pullable to the nth degree, when needed. Highlights tended to have a sharp peak, which some felt meant the DR was too limited, but I never had too much problem there as long as I exposed a bit to the left and was always able to bring up the shadows when needed. The built of the camera was light years better than the NX100. And again, the EV wheels and controls where great. Top and back wheels with iFn to round it all off. It just took forever to clear the buffer, and the buffer was very small. I wound up getting the fastest SD card at the time and that helped, but if I wanted to take more than a couple of shots in quick succession, the lockup was annoying.
Then the NX300 was released, and while at the time I was very happily married to my A57, I kept my eye on it and when Sony finally annoyed me to the point of defecting, I had a brief liaison with a 60D (plastic, no micro-adjust for focus, somewhat cheap vs. the 7D) and then jumped on an eBay deal and this time chose the 18-55 OIS III, which by now seems to be considered a wash vs. the 20-50 (plus IS). Here's my thoughts after having mine a few days.
PROS: I went with brown, and it's an attention-grabber. Not as sleek or cool as the all black metal NX200, mind you. But the modernized look with a hint of retro with faux leather wrap is eye-catching. The metal top is uncluttered and thoughtfully arranged. The 18-55 OIS III is surprisingly small and light after coming from Sony SLT and Canon SLR land, and it's very quick and relatively quiet. It has some issue with CA even in corrected JPEGs at certain spots, and I've yet to determine what that's all about, but for now I'm glad I picked it. The images are nice and detailed, a bit neutral and have a slightly more realistic hue than the NX200 did, which always struck me as very slightly cool to the green side of things. Operationally, the speed is improved, though the buffer performance can't even approach the speed demon that was my A57 SLT. Nice to see very slight on the fly RAW compression finally make the scene. That was an issue with the NX200... And WiFi on this camera is quite nice. I had an RX100mk2 for a few weeks and the NFC/WiFi on that thing is a cruel joke by comparison. I've already found myself emailing and uploading pics to FB and email direct from the camera. Hopefully, Dropbox will make the scene as soon as the NX30 shows up. Lastly, AMOLED is great as always, and now it tilts up (and flips over if you get the selfie-friendly 'M' model) and the touch function is welcome, though I'm still acclimating.
CONS: I'm starting to think the NX300 gives up a smidge of sharpness to the previous gen model(s). I have another thread on this subject so I won't go into it too much, except to say that's disappointing given my expectations having come from the NX200. Also, the build, while neat with the molded brown plastic on the back, leather strip and big tilting screen, is surprisingly a step back vs. the jet fighter semi-matte stealthy metal body of the NX200. The buffer speed is certainly improved lags my former A57 and 60D. HOWEVER, it does keep up with the likes of the Fuji X100 series, so when comparing like systems, you don't see a huge difference. Even the Sony A7 has been dinged by critics for its buffer performance... On the minor quibble side of things, I do think it's time we saw an integrated pop-up flash with the NXx00 line and the UI could be more intuitively laid out. EVF, eh. I used to hate this omission, but now I can live with it. I used EVF and OVF rarely enough on my cameras that its absence is not really noted.
OK, that's my take!