As others said, best is subjective depending on your requirements. I have had both soft and hard covers.
My experience:
Tri fold soft cover - currently on for 4 years, that came on the truck when I bought my 2020 Limited used.
- Easy on off when I need full bed access for rock, mulch, etc.
- keeps anything I need dry, luggage, camp gear, etc.
- anything will get dusty when I travel dusty roads (I bag luggage in the bed, mostly for dust or if I know I'm in a tropical storm - otherwise uncovered on streets and remains dry and clean)
BAK FLIP Fibermax - tri fold hard cover - Had BAKFLIP on 4 RAM trucks - I loved the BAK.
- I felt secure when I spent time in cities with no theft from bed (Houston, Dallas, San Antonio, rural towns/aka tweekerville)
- I'm sure a pry bar and motivation would gain access, but BAK discourages theft (as do other hard covers)
- Folds up and braces against back window for easy access hauling in full bed.
- Still pretty easy to remove. Not easy as soft, but rarely ever needed to remove it.
- Drier than soft
- Still get dust on dusty roads.. so I bagged backpacks when in desert.
- I transferred the BAK cover from one RAM to the next... finally selling it when it started to show cracks after 8 years of hard use - I could have used until failure likely many more years, but RAM changed bed slightly and I planned new top.
- BAKs are pretty expensive
When I got this truck, I thought I'd be replacing with a hard cover, but soon learned I didn't need the security since I don't travel with load as much. With soft cover, I take anything of value out at night and watch the truck when parked... minor inconvenience.
If I had to do a new cover, it would come down to cost/quality. I like the BAK. But for my needs now, I would do a soft cover for less.