Bought my Lumia 1520 10 months ago. It was the 'rare'* AT&T 32GB version. Original owner even unlocked it. It came with a decent Belkin case that allows me to tip it up in landscape mode to use it on a hard surface. I paid about $230usd for it, including shipping. I purchased a fast 128GB microSD as well to boost the storage. It had a very tiny scratch on the screen, that is never noticeable except when powered completely off.. The seller took a photo of that and divulged it, so I new what I was getting.
Finally, as of a week ago, I am running Windows 10 Mobile Preview full time on it (there were a few show stopper issues with previous releases and I waited a bit before putting it on).
With the performance and specs of this phone, I certainly will not be replacing it anytime soon with the nexgen phones.
The only complaint I have is really a WIn10Mobile Preview implementation complaint... With the 1920x1080 display on this phone set to 3 columns wide (yeah I could have gone 4), they (Microsoft) seem to have defaulted to too small of a font size. Defintely noticeable going from WIn8.1Phone to Win10Mobile. (At 4 columns wide, things get pretty small...especially on the smallest tile size..but that's to be expected.)
* the 32GB is indeed rare. I looked for two months. purchased 2 of them, only to have them arrive as 16GB models. I dislike misleading advertising, so I insisted on returning each one and getting a refund. Ultimately, I required sellers to post screen shots of the actual reported storage. A few couldn't be bothered. One fellow finally did and I purchased his phone. Beware of all the misleading Ebay listings that call the phone 32GB... especially if they list any color other than black (the 32GB AT&T model was only available in black).