I am looking at ordering some unflavored liq nic to DIY. I am wondering if someone could tell me if you think that buying a higher concentration and cutting it ends up being less in quality and effectiveness than just buying the lower concentration to being with. Also is there any difference (other than the pg/vg added) in the types of liq nic available out there? Meaning other than the vendor's customer service and shipping are these pretty much the same product? I see a few sites that have bottles 16oz and larger. Wondering if there is any reason to buy a small quantity to test it out first or not. I assume they are much of the same. Or does anyone have recommendations on vendors with good rates on larger bottles?