With complete disclosure, I can state FLIR, who I work for, does offer the entry level DNR204 and DNR208 Series NVR/POE. We also offer the DNR308 and DNR316 Series NVR/POE (only 8 POE ports). Coming soon will be 16 Internal POE Ports, but in the mean time we sell an 8 port POE switch with a separate uplink to solve the extra POE requirements.
A separate discussion could be "Why are they popular" and "Where do they apply." I can hear the crowds yelling "it fits the trunk slammer perfectly." Maybe so. I had a conversation with an IT Director recently who saw the value in these for his 100+ locations. Is that a trunk slammer sale?
Having the POE built in, which is usually powered by a separate supply than the NVR itself, reduces the amount of cabling required and simplifies the connectivity. I would suggest anyone installing these purchase an Extech CT-100 cable tester also (another self promotion as FLIR owns Extech). Cat5e cable seems to run about 70% or so of the cost of a Siamese RG59/18-2 cable. It's also easier to pull from my experience....and I ran a lot of RG59u in my life.
Having the ability to add cameras using the subscribers LAN is a bonus when cabling a large building and the IT department has already provided a decent back-bone. At that point the IT guy is usually involved and can manage addressing and routing for the less technical installers.
Let's face it, even an average 720 or 1080p image in decent lighting looks far superior on the customers HD flat panel monitor which is now cheap. So cheap that it is driving this change. When television was SD, Security could be SD, now that television is HD for almost all, Security has to be as well, even in the least demanding environments.
Fear kept many from embracing IP technology and these kits or packages remove most of the fear. Many of them are so simple they almost set themselves up. Cable the cameras, plug in the cameras and unit and watch the images appear. Just like an SD DVR but clearer. Less fear. Techs only need to walk through the easy setup sheets to make it accessible to the end user via a remote device such as Android / iPhone / PC and Mac. Those requirements are there even in a DVR these days.
One of the limitations of these low cost NVR solutions is still the bandwidth available throughout the unit. How many images per second and at what frame rate will be confusing to some or not clearly defined just like when DVR's first appeared. Which cameras are they compatible with will be another. Do the units share the network between the cameras and the NVR or are they separate? Does the unit Auto-Address the cameras?
In one of those separate discussions I will outline how an IT manager for 100+ locations found value in these systems for those who think it's only going to be popular for homeowners and "Stop and Rob's."