At first, the taste is excellent but a few puffs later it sort of tastes bad. Is that an inidcation that I've gotten all that I can out of what I'm vaporizing or should I keep puffing despite the less pleasant taste?
This is normal with any direct draw vape. As you continue to hit the bowl, you're heating herb that's already been vaporized, so the taste goes south in a hurry. The only solution is to load a small amount, which doesn't give you much satisfaction as far as hit size, so it's tradeoff.