how different is colli 915 to the 845 ?
In what sense? Application,durabilty?
915 is a paste wax, easy to apply and remove, nice finish, I've not done durabilty tests on it yet so cant comment on that one.
845 is like a gel when cold but once warmed through its a nice silky viscous liquid with cream colour tinge to it, applies super thin and goes on like butter, needs to be used with caution on hot/warmer sunny days as it can weld itself on and be a pain to remove if left too long,cures very quickly in these conditions, hence guy saying its very user friendly in the winter months due to lower temps etc.
I've seen a solid 9 months out of it but I'm sure it would go on for longer if I hadn't started testing other products from then onwards.
I use this for winter protection details, a good bang for buck wax imo.