I would recommend the apple garde, it’s made in the USA and is liked by many people. It also would, in theory, be much more effective than LMB because it is an actual hydrophobic coating on top of the Vachetta which prevents water from soaking in. I have even poured cups of water on smaller pieces with Vachetta to see how effective it was and it just beads off. As it is a coating it can wear off and needs to be resprayed at least every few months. Depending on the age of your bag (meaning how open the leather’s pores are and how much patina it has) it will darken the colour of the leather either somewhat or to an extreme extent but will dry within a few minutes (if you use too much or it settles to one part of the leather it may take a day or two to completely lighten, but it will lighten, do not worry (note: do not wear the bag until a few days have passed). I have one of those very rare all Vachetta bags that Vuitton used to take custom orders for and have even used it on that piece so I would trust it on anything with Vachetta. It is basically the same thing that us men use on our suede or nubuck loafers if we wear them out when they could get wet. If your bag is older and the leather is dry I would condition your bag using a small amount of an all natural leather conditioner before the waterproofing. Make sure the conditioner is not bad for natural leather and has no negative components (lacking silicones, artificial waxes, and oils etc) I always recommend Saphir renovatuer which is a great conditioner made in small batches in France. Stay away from Cadillac brand, kiwi brand, fieblings, or anything labeled as for automotive use or for leather upholstery.