The cecal poops happen I think every 90 minutes or so, I don't recall the exact timing. And they STINK! BAD! No way getting around it. Regular poops do not smell as bad.
I have done the fermented feed and didn't really notice much difference in smell, though I know lots of others have. Maybe my particular local flora (that makes the fermented feed) isn't prone to reducing odors. I do still feed some fermented feed, but it isn't their sole food source.
Some folks go to great lengths to reduce poop smells, things like:
* poop boards (under the roosts, cleaned daily or weekly)
* poop trays filled with sand (under roosts, poops scooped regularly)
* using Sweet PDZ under roosts and/or in the rest of the coop and run (bedding material mixed with a mineral that absorbs odors)
* completely cleaning out the coop every day or week or month
I don't bother with those things. We do have some smell, but it's never all that bad. Probably because it is so dry here that the poops dry out quickly. About once a month I do spray the interior of the coop and run down with a probiotic brew I make. The microbes in the brew help cut down smells. In fact, for a few days after the spray-down, I can't smell anything much at all. I'd do it more often, but I am lazy and once a month is enough for me (since the smell isn't bad to begin with). We also live out in the country where we don't have close neighbors that might not be as tolerant of the mild smell as we are.