Bring one DSLR and one compact and the 16-300mm lens, depending its size and weight. You have to decide if this is a photo trip, with allowances made in traveling for taking time to set up and adjust, or if it is a pleasure trip, during which you'll take pictures. If you're on a tour, how much leeway will they allow for your to chance lenses and cameras and change settings. On a tour of China years ago, most people were fast with their photography, but one woman with a DSLR kept everyone behind her waiting while she got the best shot ever taken by a camera.

I am surprised by the single card slot choice. But my first 7 years with a DSLR (2010-2017) were spent with a single card camera (D5000) and I never felt any kind of lack. Since last year I’ve had my D7100 and 2 cards. Since I use one card for JPEG fine and the other for Raw, I see it only as a convenience (I use the JPEG images mostly SOOC — occasionally cropped — and Raw to post process) so even with my 2 cards I don’t have a true fail-safe backup for card failure and frankly I don’t see that lack as a deficit.

The article does mention using and adapter for a DSLR lens on a mirrorless camera. If the flange-back distance is less with mirrorless, then it's possible. I think it's a given that Nikon will have to offer such an adapter. So the question I have is whether that expensive 2 grand zoom that someone just bought will work on the newer cameras without any loss of functionality/speed. I think it's given that Nikon lenses that require a focusing motor in the camera, some of which are still made, will be pretty much dead in the water. I think that initially, these cameras will appeal to people with a lot of money or those who don't have a lot invested in the older technology and first time buyers.

It all depends on what you mean by "replacing". In new camera sales, MILCs are doing pretty well. In the installed MILC/SLR/DSLR base, they are a much smaller part. Obsolescence, either technical or physical, will be the major determining factor in when SLRs & DSLRs are removed from the population of cameras at work (pro or otherwise). Think of how long it took to get the cars from the 1960s & 1970s off the road. Newer cars did not replace them as they just went used market, but sooner or later, they just quit working.

Now, with DSLRs, let's look at my installed base. I have a D70s, D200 & D500. I also have a X-T2 MILC. The D70s is pretty much obsolete, technically, and is reserved for training grandkids - it still works, just at 6MP with the noise profile of a ~20 year old camera. The D200 I still use, mostly as a backup or second lens camera to support the D500. I look at DSLRs like computers. In the 1980s, you had to buy a new computer every couple of years as the technology advanced, by 2000, the Pentium had come in and computers lasted much longer. Today's computers will last a good long time before they require replacement. The D50/D70 era was the early age of DSLRs, they were underpowered and needed replacement fairly quickly. The D200 still works fine, if there is enough light - same as always. Over 800 ISO, it is a noise master. In the lower ISP range, it puts out fine images. The D500 works well even in low light. For what I shoot, it should last many, many years. Yes, new tech will come out, but the D500 with my pro-level glass will continue to put out fine images.

I bought the X-T2 as a briefcase camera as it is small and light and can cover 18-200 with 2 small and good quality lenses. If forced to pick between the D500 & X-T2, I would go with the D500, but I am enjoying the X-T2 quite a lot. BUT, the X-T2 has not taken the D200 or D500 "off the road".

Sorry PVR8, you need to look at the numbers and the market graphs, it is happening already that mirrorless is replacing DSLRs. Many DSLR users like you are just in denial about reality. You have never used the latest mirrorless , or you would know the truth is they have significant advantages that NO DSLR can EVER physically have. That is why pros and amateurs alike are switching. And that is why Nikon and Canon are putting their best money and tech into new fullframe mirrorless systems. Nikon's debuts tomorrow, Canon's debuts likely by Sept. 4.

You are so wrong and uninformed. All mirrorless companies DO NOT manufacture DSLR cameras. But the major Japan Camera Makers Executives at latest JCM convention publicly stated that the reign of the DSLR is over and mirrorless is the future, here now. DSLRs wont disappear overnight, but their dominance is over, that is just reality.
Your lack of any real knowledge here is truly sad.