Potentially stiffer soles, although you can of course get stiff MTB or touring shoes, lighter in weight...although light not necessarily good in winter. Bigger surface area of cleat may prevent hotspot. Some people prefer the look of the shoes and the
pedals on a roadbike
Downside, you can't walk so easily as the cleats aren't recessed
People do long distances in all sorts of shoes, depends what works for you
I looked at SPD-SL but I have awkward wide feet and couldn't find one pair of shoes from any brand that were comfortable!
Also I can't abide single sided pedals, which all road ones are. I ride mostly in traffic and have to clip in and out a lot, the pedals being the wrong way round every time used to do my head in! Shimano M520 ftw
There's a sticky on this which may help
https://www.cyclechat.net/threads/clipless-pedals-faq.74358/