I used this for the first time yesterday on a black car, and all I can say is the product is extremely easy to use and the end result is great!!! My 2c worth anyway.
I am really curious to try Megs 16 since it seems to be a great reliable LSP to have on hand. I just have way too much LSP right now and that includes every Collinite wax/sealant which will last me a life time. Do you have any Collinite to compare #16 to?
M16 is a pretty good wax that does is durable. But, IW 845 outlasts it by a good bit in my experience. They both look good and I must give the advantage to 845 there as well but not by much. They are both good waxes and can't go wrong with either. That's my .02. Hope this was helpful.
if there's a difference in durability between 845 and 16 i can't comment, but the difference in looks, imo, is that 16 is a little bit like a carnuba as compared to 845 which give, imo, a more sealant look. both are excellent lsp's.
I've been wanting to try some M16 for a while now. It's becoming harder and harder to find. If anyone has an extra tub they'd like to sell or trade for, PM me.