I have one. I have not had the opportunity to compare it with the 8x56FL, nor any 10x HT nor SV so you might want to quit reading, but I will try to make a useful comparison with the rest of my collection. I have 8.5x42 SV, 8x42 FL, and Fujinon FMT-SX in 7x50 and 8x30, all which beat the 10x56FL in pure what I'd call apparent image quality. The 10x56 FL, however, beats quite badly, image quality wise, my12x50 Trinovid BN which reveals only equal detail (but is arguably too much magnification to profitably hand hold), and narrowly but certainly beats a 10x50 Ultravid BR. It also beats a 10x50 FMT-SX I once had. And my 15x60 Docter Nobilem, which in turn murders the 10x back in detail revealed, given sufficiently steady holding.
My take is that high powers beat low powers in detail rendered easily visible, provided conditions allow for calm and steady holding. But, low powers beat high in apparent image quality. In fact it seems to me that magnification is the greatest single determinant of "apparent image quality". For example, highly experienced binocular folks RAVE about the image quality of the cheap and flimsy 6x30 Leupold Yosemite and its various clones, not much the 8x.
That said, the 10x56 is a "superb 10x", with high transmission, excellent mechanics, and extremely precise optical adjustment, as I see in its performance in stargazing, especially on marginally splittable double stars, an acid test for sure, of it and me.
I guess the choice between 8 and 10x FL depends on whether your applications would allow the high power to shine, and whether you are more an object detail or image quality buff.
Ron