It definitely depends on the vape. Some companies mix the cannabis oil with fillers and additives such as propylene glycol, coconut oil, vegetable glycerine, or add food-grade artificial terpenes or other flavoring that can be a serious irritant when inhaling. I would recommend trying some vape brands that have NO additives to eliminate this cause of harshness. Only pure cannabis oil!
As for the flavor, we have worked really hard to perfect our extraction and post-production methods to preserve the terpenes (which give each strain of cannabis its unique taste), which is a signature of our brand. Incredible flavor. At a minimum, when buying a vape cartridge, make sure that the company implements a "terpene separation" process, which would signify that their process aims to preserve the flavor element. The terpenes are a most sensitive components of the plant that are easily destroyed in the extraction process if special efforts are not made to preserve them.