I've been perusing the many posts about PP versus polyethylene etc when it comes to shrink wrap for votives, tarts and pillars so I'm pretty sure I understand to use polypro. However, I'm also reading on supplier sites that they use PVC? When I try to Google it for more info I'm not getting anything. Is PVC shrink wrap good, or bad? Does it leech away the scent too? I was going to get some from ULine or All White Candles but they both offer PVC. Help!