Snell speakers kIII and type d

I just recently helped and older couple move into a smaller home and the older gentlemen was going crazy about these speakers and how great they were. All I really knew about them were that they were so heavy!! Well by the time we were done and they didn't have money to give me( which I didn't expect.... At all) but insisted I take this whole set, which I tried to deny multiple times because all he did was praise them. But he wouldnt let me leave without them!!! He says he doesn't have the room nor the ears for them anymore. I have 2 type d and 2 kiii along with sub550 and rotell surround sound

So 1....just curious about what's so great about these speakers and do people even enjoy them anymore?
And 2.... how much could I get for them if I wanted to sell them invidually and/or all together