And to be clear - I've just seen the one reference to the possibility of Reno not being good for shell. I'm not certain it is, or isn't. I just ordered the Saphir cordovan wax in neutral (for all my shell shoes) and will also be reporting back. Regarding shell's tendency to dull out quickly, yes. This dulling is the result of oils coming to the surface. As you mentioned brushing vigorously brings them right back up to looking great! I also find that rubbing quite firmly in small circular motions with a clean dry soft cotton rag brings up a beautiful lustor in less time. As the shoes age a bit they will dull out much more slowly, as they will dry out more. The finish will get harder and slicker (if you have diligently worked on their care). This is shell at it's best. Eventually, of course you must add oil back via conditioning - but less is more in general. You'll know how dry they are, or are not, basically by noticing how many wearings it takes for them to dull up.