I have been using a pipe zippo for some time now and overall I love it. Really you just need to learn how to use it, much like we all learned how to smoke a pipe properly. At first I didn't like it much but came to find the problem was myself.
Overfilling is a biggie, also the fluid problem of longevity. I started to us a rubber strap that fits tightly over the lighter that I roll down when I want to use it. That helps preserve your fluid, a small smear of petroleum jelly along the indents on the lower half of the insert helps. I went from filling it every 3 days to every few weeks!!
The taste issue... Very seldom do I detect it anymore. My first few bowls it was prominent. Possibly I have become accustom to it? Premium fluid is supposed to taste less.
Bottom of the bowl issue... I notice a pipe with easy draw helps, like a cob. I skimmed the comments above and noticed the tilting of the pipe was mentioned, that does help.
I love the zippo, I feel like I am seen as a green leaf smoker when lighting my pipe by others. Lol, weird I guess. The click of opening and shutting of the lid, and the soft flame is a plus. Although I have noticed some of my pipes get scratched from the chimney. Just carelessness on my part perhaps.