I recently bought a Blackview Chinese special from Amazon in the Black Friday sales. It cost the princely sum of just over £43 new.
It's not a premium smart phone, but the screen res. is the same as the mid-range HTC it replaced. It's only 3G and does not have NFC, but I found that I was not using the NFC and 3G is quite fast enough for the limited amount of mobile browsing I do,
It's got the same Flash and RAM, and Android 7 appears to do a much better job of managing the available memory than previous releases. The battery is removable and large at 2800mAh, and easily lasts more than two days the way I use it. It has a microSD slot as well as the SIM slots.
Also, the call and audio quality is much better than the HTC.
But the main reason I bought it was that I had been carrying around two phones because of coverage problems (the other a Nexus 4 running Ubuntu Touch - which worked really well), and this Blackview is a dual-SIM phone that means I only have to carry one.
All in all, it's a perfectly good phone for almost nothing. The only thing I still intend to check is whether there is any traffic from baked-in apps on the phone, but I've not noticed anything yet.