The wooden shank does affect the flavour for the first few bowls. You can break the shank out of the bowl. I use a straight screwdriver I sharpened with a file. I just carefully break and gouge the shank until it starts coming apart and falling out. When the shank is out you put pipemud in the bottom of the bowl. There are a lot of really good instructional videos on youtube that shows the procedure. A smooth bowl was covered in plaster-of-paris and sanded down, then it gets a coat of varnish. The rough bowls are just natural. The plastic taste is probably from the stem. Vermont Freehand.com has some fantastic "forever" stems for sale for MM corncobs. With the VF stems a cheap corncob becomes a really great pipe. I've had a few of mine for years.