I own a 4 pack of Swann cameras with a 2 tb DVR. It works descent considering the entire setup was less than $1,000. anything beyond 20 feet is garbage and you will need an ac adapter to power each camera. I will be adding and IP camera soon to test the strength/weakness of each. With an IP camera its powered via the Ethernet cable which makes wiring and installing camera much easier. Especially through conduit. I assume the software is proprietary to view/record. I have seen some pics from porches which looks like hi quality images and it can be connected directly to my pc which is connected to my tv. Another bonus if I want to switch back and forth. They both allow for remote viewing however hacking into my pc is a concern (the hard drive will either be inside or usb). With a DVR everything is separate.
Not sure what other differences there are.