Sometimes the extra bounce from suspension forks can make the handling of a bike feel squirrelly on a rocky path but are nice on a paved road.
Hmmm... If you find suspension forks squirrelly off road, then they may need to be adjusted. Riding a rocky path
without front suspension is the very definition of harsh and squirrelly. The rocks bump the tire up and out of contact with the road, decreasing control. Properly adjusted shocks absorb bumps and rebound, keeping mountain bike tires in contact with the path, maintaining control.
I just installed shocks on my Stromer after riding over single tracks and fire roads on the stock CF forks. The handling is much more sure footed with the shocks. However I won't be riding the Stromer on single tracks again. It just isn't agile enough for them, but rutted dirt fire roads are a lot of fun now.
@Ann M. is correct that low pressure 3-4" fat tires will give you a cushy ride anyway. If you are going off road on rocky trails I'd get shocks too. But if you're just riding around town, on the beach, or smooth trails then shocks won't matter much with those tires.