This has been discussed here before, and as I recall, the most efficient feeders are the cone type with the skirt. But, I agree, haylage vs dry hay makes a difference too when it comes to waste.
Now even though my hay bales were baled with a silage baler. I don't wrap them in the plastic material so that the hay ferments and becomes silage.
So other than the hay being chopped up in the baleing process. The hay is dry hay like any other dry hay.
But because my bales are chopped up like they are after being baled by a sialage baler and are feed using the skirted hay rings plus using the slanted bars spaced about 2 foot a part is the only reason i have very little hay waste.
The three key things that makes this way of feeding is the chopped hay, slanted bars and spacing, skirted bottom around the feeder.
One other thing matters too is the weight of the ring feeder. These feeders made from plastic tubing or light gage metal tubing gets scooted around of flipped over easy by the cows allowing them to trip the hay into the mud or they lay on it, crap on it etc..., then they won't eat it and it goes to waste.
That's what happens too when you feed hay baled by a conventional feeder verses a silage baler. The hay baled by a regular hay baler becomes sort of tied together by over lapping and being wads of grass so the cow has to pull it loose as it gets a mouth full of grass. And is constantly pulling the hay outside of the ring feeder while it eats. Then that hay gets stomped into the mud, crapped on and is wasted, cow won't eat it.
The chopped hay from the silage baler just falls to peaces after the net wrap is cut off. When the cow takes a bite only what is in its mouth will come out of the ring feeder. The skirt keeps the chopped hay from spilling out of the bottom. The slanted bars has each cow at the feeder eating to the left in its own area. And the weight of the feeder keeps it from being scooted off of the hay. 90 % of the hay or better is consumed by the cow.