1) It works in Linux. Other, simpler scanners (non-ADF) can frequently work OK in Linux, but the Linux scanning software is a bit of a mess. I use gscan2pdf at home which works well enough, but looks pretty rough and hasn't seen any updates in years. But ADF scanners are different because of their nature; I'm not sure it'd be easy to get existing software to work with them, and I don't think the SANE interface works with them. With VueScan, you just install it, plug in the scanner, and it works, at least that was my experience. It has its own built-in drivers for ADF scanners like the ix500.
2) On Windows, it's just better. The Fujitsu software was a complete nightmare; it's horribly bloated (I seem to remember it being a 500MB download!) and very difficult to get working. I'm not sure it even works in Windows 10. VueScan is not a big download, and like on Linux is simple and easy. I haven't done much with it there because it puts big ugly watermarks all over your scans with the trialware version. But if I had an ix500 of my own, I'd be buying a copy of VueScan; I think it's only $20.
Luckily I don't have to do much scanning, so I get by OK with gscan2pdf on Linux and my now-older CanoScan LiDE 50 (I think that's the model number, or is it 25? I forget now). It's slow, and a bit of a pain as I have to haul it out and plug it in, but it works reliably and decently. But if I were doing any volume scanning on a regular basis, I'd break down and buy an ix500. They're very expensive ($500 new I think, and used ones on Ebay usually fetch over $300), but I've never seen anything like them: they don't take up much desk space (they unfold out when you need to use them), they have excellent scan quality, and they're ridiculously fast, while also doing duplex scanning just as fast (using sensors on both sides). They also don't seem to have any trouble with misfeeding pages.
