For the most part, people over analyze all this genesis stuff. If it's not wicking, make sure you have the fill screw out. They just don't wick well with it in (no matter what people tell you). I've used mesh from 325 to 635 in solid and "tube" configurations and I'll be damned if I can tell that one works better then the other. As far as a metallic taste, that is usually from a short or micro short, a loose coil or the top leg going to the positive post being too far from the post. Make sure the top coil is close to the post but not touching, then poke the coils during a dry burn to make sure all the coils not only glow evenly, but heat up at the same pace.