Thought I'd share my experience with this recent purchase.

I ordered the Dahua IPC-HFW4300S (http://www.dahuasecurity.com/products/ipc-hfw4300s-398.html) camera and the Dahua NVR4104-P (http://www.dahuasecurity.com/products/nvr410441084116-p-675.html) NVR.

The camera ended up costing NZ$145 shipped and the NVR was NZ$268 shipped.  I'm also using a Western Digital 4TB Purple WD40PURX hard drive which seems to run well so far.  The NVR can handle 4 cameras which I'll be adding over the next few months.

I purchased these items from two separate AliExpress stores: http://www.aliexpress.com/store/202753 & http://www.aliexpress.com/store/809300 - both items arrived approximately two weeks from when I placed the order.

This is the first time I've dabbled with CCTV and it was relatively painless to set everything up.  The NVR has a lot of nice features and the camera has been excellent so far.

The only negative was the dry wall expansion anchors that came with the camera - they didn't work that well so I ended up buying some self drilling anchors from Mitre10 which worked far better.  For an explanation of expansion vs. self drilling anchors, this video helped me: https://www.youtube.com/watch?v=kFLxQ9aNlrY

I hadn't used AliExpress before so chose merchants with good feedback.  I hope this post helps others who are contemplating ordering from AliExpress or might be looking at Dahua equipment.