isopropyl alcohol is cheaper. I’m an RN and use those alcohol wipes on the hubs of IVs and on IV line spikes and such. I figure if they’re considered safe enough for sick people, they’re safe enough for my purposes and I do take care to ensure that no isopropyl alcohol is ever introduced to my final product. I don’t think a tiny bit of it would matter one bit but I still go to lengths to ensure it doesn’t happen. I go through lots of scalding water too. Those carboys are completely sterile when I’m done and I keep them that way throughout the fermentation and bottling process. My bottles are just as sterile as the carboys too. I briefly soak my corks in alcohol initially and then wash them off with scalding water. I then soak them in a sodium metabisulfite solution and I make sure they’re still wet from that when the cork goes into the bottle. that’s the only metabisulfite I add to the wine. I like to think that my great pains at maintaining sterility precludes the need for excessive metabisulfite. Ya know, I think I’m going to open a bottle up. It’s 1:41 and I don’t have to work tonight. cheers.