All of the personal mess kit components (personal utensils, dishes, cups) are provided by each scout, so we have a wide variety of implements used.
I personally don’t like the sporks/double-ended utensils. I just find them awkward to use. I know other folks in our unit who swear by them.
I use a plastic spoon and a large sierra cup for pretty much everything unless I’m snow camping, at which point insulated dishes become valuable. I do own the plastic knife and fork to match my spoon, but I seldom end up using them, even if I do remember to bring them. Usually, if something needs cutting other than with my spoon, I bring out my pocket knife.
In terms of material, I know people who have broken the heavy-duty plastic utensils, whether single-purpose or combos/sporks. I’ve been using basically the same plastic utensils for over a decade and never broken one. Some of our scouts/leaders prefer metal utensils for durability, but personally I feel like I can’t justify the added cost vs buying and bringing an extra spoon for another $1. :^)