FPGA NES: http://www.retrousb.com/product_info.php?cPath=36&products_i...
Main difference between the two linked products, then, aside from appearance and maybe build quality (can't say which is better, don't own either), is output options, as best I can tell (the NT has a lot of AV out options). And price, obviously.
[EDIT] The reason video out options are important, aside from aesthetics, is that some peripherals require a CRT. Notably the Zapper.
Emulated, but from what I understand, not perfectly. Mainly because the SID was a hybrid digital and analog IC - and it's that analog part that made it unique.
Also - I don't think (I could be wrong) that any successful reverse engineering of the chip was ever done, nor do I think that there were any or much documentation about the chip (that is, official docs)? It was very much one of those custom chips made for one specific purpose that wasn't used in any other product (this was a common thing in many home computers of the 1980s).
I know little about the Apple 2 series, but in quite some C64 software, these operations are used wherever they can save a few cycles. Mostly demos.
(Note that Goodwill recently updated its web site and apparently kicked many of the regional organizations out, so supply has been lower lately. Hopefully when the regionals get up to speed the supply will increase again.)
* The (epoxy-potted, non-serviceable) power supply fails (and the resulting voltage increase takes out the 4164 DRAM chips). * The PLA is not heatsinked, runs hot, and fails. * The MOS replacements for standard 74xx logic chips are notoriously unreliable.
You're better off finding a used one that's been tested with a TV -- "powers on" is not enough.
In addition, the Goodwill ones (at least in the USA) are NTSC, whereas a lot of the later European games were PAL-only. If you want to play those games, you end up having to find a cracked, NTSC-fixed version of them.
How can you put the original hardware into a case that is half the size? There is no way that the bits inside the case of my recently revived C64 would ever fit into this thing. Even if they cram a "real" SID and VIC etc into it then at least the motherboard and rather a lot of other things have to be rather different.
Unless you're aiming for accuracy, it's a lot cheaper to simply put a cheap little SoC on board, cover it in epoxy and ship it
https://icomp.de/shop-icomp/en/produkt-details/product/c64-r...
All you need is the chips from a dead old one.
What are the challenges in producing new C64 (and NES and SNES) with the same hardware? I believe there are a lot of modern Genesis copies using the same hardware.