mirroless or dslr?

For most of my shooting needs, I go with a dSLR. I only use a mirrorless for concerts when I'm seated far away in the upper boxes.

For city and urban folks, mirrorless with EVF is a good choice. It's also good for studio shooting, the only time I used live view with my DSLR so I can do critical focusing.

For wilderness use, I find DSLR to be superior due to battery life and optical viewfinder for moving wildlife. Having a DSLR respond quickly is a major benefit when waiting for wildlife. A DSLR doesn't need to be turned off unless traveling, thus is always ready to shoot instantly. Also, I don't have experience using mirrorless in cold temperatures (around 0 deg F), so don't trust the technology yet.

There are advantages and disadvantages to both. Eventually mirrorless will take over but that's a long way off.

The electronic viewfinder (EVF) on mirrorless cameras provides a preview of exposure and may aid some users seeing in very low light, but it suffers from lag (varying between models, but they all do), making it harder to capture a finely timed shot, and all the time they're in use drains power.

The optical viewfinder in a DSLR has no lag and can be used to examine the scene for extended periods with no power consumption penalty. In skilled hands, a DSLR cannot be beaten for responsiveness. Exposure can also be previewed on DSLRs using live view, but as this employs the external display it will be harder to see clearly in bright light than an EVF.

Some people buy mirrorless for a reduction in bulk, but don't always factor in the lenses. The range of lenses and accessories is also much greater for DSLRs as they are a fully matured market.

DSLRs are becoming less and less desirable over mirrorless cameras. Mirrorless are smaller and lighter. Mirrorless can accept any lens from any brand via lens adapters. Some DSLRs, like Canon, can accept Nikon lenses via a lens adapter. However, you cannot put Canon lenses onto a Nikon since the distance from the rear element to the plane of the sensor would be too short.

Many mirrorless cameras have in-body image stabilization while only Pentax has IBIS. Canon and Nikon both use the less desirable in-lens stabilization. IS requires additional lens elements which makes the lens heavier, more expensive, and because of the additional lens elements, the lenses are less sharp than non-IS equivalents. The Nikon 24-70 f/2.8 vs 24-70 f/2.8 VR is a great example. The non-stabilized version is lighter, costs $600 less, and it's noticeably sharper, too.

With the exception of the Sony A9 and A6500, mirrorless cameras can't track focus as well as a DSLR. So if sports, action, wildlife, etc... is what you want to do, then go with a DSLR.

With the exception of high mirrorless cameras, the EVF in mirrorless cameras have a lag between what you see and what's actually happening. This lag will makes the camera awkward to use and will cause you to loose action shots. But on the other hand, the EVF shows you the exposure before you take the shot which is something no DSLR can do.

The EVF can also show you the point of focus which another thing an OVF in DSLRs cannot do. This makes working in very low-light situations easy for mirrorless users and difficult for DSLR users.

Personally, I currently use a DSLR type of camera, but if I were to buy another camera I'd go with a mirrorless with IBIS instead of a DSLR from Canon or Nikon without IBIS.

For the reasons that I noted above, Nikon sales have tanked, especially their DSLR sales. The market is showing that DSLRs are not as desirable as mirrorless. However, there are legitimate reasons why you would have to go with a DSLR. It really depends upon what you shoot and, of course, your budget.

Depends, mirrorless uses up battery charge quicker than dslr, but dslr is more bulky.