They definitely don't. The advantages to distillate pens are they're discreet, low smell, tasty, and get you pretty high pretty quickly. But they really aren't cost effective. A half gram oil cart in the California north bay is $25-$35. A cart package I have here says it contains 420mg THC (presumably they derived that concentration on purpose). A top shelf eighth is $50. Let's say the strain is 20%. That's 700mg THC. So dollar for dollar the oil is looking good. BUT, it's only THC and terpenes and lacks some cannabinoids that help you get higher or feel high in different ways. Also, flower goes on sale. Carts/distillate prices are pretty much fixed. I just got a half oz of pre-ground 15% flower (2100mg THC). It was $35. So I got five times the THC as a distillate cart for the same price. It just wont taste as good.