Sounds like you'd prefer a Euro-gun, if not though, have you considered a South African railgun, such as those from Rob Allen or Rabitech (I notice there is at least one other now)? You can order them with single 16mm, double 16mm or single 20mm rubbers, most models include a muzzle that will accept a second rubber band (if not already equipped) & double notched spear. (Bulk rubber bands, Dyneema wishbone, rail, muzzle bungee & clip, & handle clip). Miles owns many guns around the 110cm size - you might want to take a look at some of his previous posts, where he included pictures of his collection (including a C4 carbon gun).
Re. Dentex. TV Chef Rick Stein was on TV last night, eating Dentex on the Med., reckons it is even better than Bass! Must be good
