I have cement board siding from a national big box store and I absolutely love it. I would never install vinyl. The cement board looks like wood, holds paint way better, never needs power washed, never buckles or looks like a Ruffles potato chip when you sight down a long side, etc. It does have some drawbacks though. It requires more tools to install. I use a circular saw with special blade to cut to length. If you use "green" cement board, i.e. fresh stock, you can pound nails through it with no problems. Once it cures with age, you need to predrill it especially if you are nailing a small piece or close to an edge. Cured cement board also become fairly brittle so you want to keep it covered and out of the sun during the installation process and any leftover pieces are about useless in a couple years as they will shatter like a plate. It does require painting and the vinyl people always used to tout that their product doesn't but as we have seen with time, plastic fades with sunlight and exposure to the elements so while it never needs painting, it does change color and look worn out with time. I have a ranch style house so painting my siding once every couple decades doesn't cost a lot of money nor take a lot of time. At my age, if I continue to live here, I probably only have one more painting left in my lifetime and then it will be someone else's problem. The caveat of course is that I use high quality primer and paint that costs 3 to 4 times what you can buy store brand big box store paint at. Thus it lasts a long time. If you buy the cheap stuff, you will have to repaint much more often. Finally, I have had a friend install cement siding on his house which heaved during an exceptionally dry year we had and it cracked along one side from top to bottom. It is repairable and from a distance isn't noticeable but it definitely isn't as forgiving as vinyl. That's not to say that vinyl siding would have buckled and looked terrible too, but it wouldn't have cracked. I probably wouldn't install cement board on a brand new house that hasn't had a chance to settle. But for an older house that has settled and not likely to settle anymore, I would most definitely pay the premium to have cement board over vinyl.
