Ive been making hash over 20 years now,i gave up on butane hash,not because there isnt a difference in buzz but from the danger aspect,i had a bad experience with fire so now all i do is ice hash.
With that said ive made hash from dry cured bud/trim,from dry uncured bud/trim,wet bud/trim,frozen bud/trim & frozen cured wet bud/trim,out of all these methods i saw no difference in quality or appearance.
If your doing it properly dry veg material should not be an issue,if its filtered properly no particles of veg matter should be in the final product,you loose some thc to the filter process but fuk it,i want pure.
One thing i know to be a huge digference is with ice hash not having much of the essential oils containing cannaboids from within the leaf/bud,this is the main difference between ice hash & butane hash,you can overcome this.
I make ice hash with wet & dry material,it just depends on what i have going,when working with wet material i pulverize the material into a pulp,this releases much of the oils from within the leaf & bud,after pulverizing i use regular ice hash procedures,i much prefer this hash over my dry material ice hash,it has a different buzz & is very close to butane hash,you just have to pound the shit out of the material to release the oils.
Something else to consider when making hash,i see lotsa guys making hash from bud that is for one reason or another premature,for good quality premature bud should not be used,if the bud is too early to smoke its not ripe enough for good hash.
You want as much ripe resin as possible for hash,amber trichomes make for knock out punch weed,same goes for hash,clear trichome hash has a much weaker effect,short term buzz & can give the smoker head aches,all the rules that apply to bud being ready apply to hash.