Hi Britta – Thanks, yes I think the effect is probably my favorite. Over time the only change I have noticed on a wallet is that it takes about 1 week for the vinegar smell to go away, then everything is back to smelling like leather. As far as appearances, it should get slightly darker over time with use (rubbing, oils from the hand). Also – make sure to apply some sort of wax to the leather after application, this helps the leather a lot. I use a mixture of walnut oil and beeswax – mostly walnut oil so it is easy to rub into the leather.