Yup buy locally or it's all markup china stuff. Some companies order in bigger amounts from china so they can have better quality control which is why they charge more for what looks like to be the same exact product.
I recently saw an ice cube tray that makes ice designed for rigs and bongs. I can't find the link but try a quick google search. it was a silicone ice tray for bongs.
yup I agree with all the above post, shouldn't cause problems just might shorten life span. Ive had a few custom pieces arrive with bubble and they last forever