How do y'all feel about needle selection? I think an 18 is easier to fill and easier to empty but is a big hole and they scream as if I stabbed them with a dull stick. The 22 they hardly notice but takes forever to fill and hard to empty into the goat. 20 may be the perfect combo. The only thing I do sub Q is ivomec +. It is thick and stings. So I am torn between big needle and get it over with quick or small needle so the puncture hurts less but takes forever to squeeze out the liquid.