a lot of dealers i know dont even sell 3.5 for 20 quid.

most are gready so and so's and would sell you 3 grams.(that aint bad)

go to rudeboys and get between 2.5 and 2.8.i also hate the way they grind up their weed to dust before selling it.you never know what you are getting.i know some that will grind up all the twigs as well just so theres no wastage.