You know the little plastic cheap ones by the cash register at your local B&M?? That's what I use. Never failed. I don't dilly dally around with it. I put the cigar in the little slot and snip it with purpose. Narry a problem that I can recall. Sometimes, if I want to get fancy, I'll even twist the cigar after the first V cut and do it again for a crown cut. Still no problems. $5 and if I lose it, so be it.
I used to be a punch guy but I like the V cutter better. Actually less fuss, IMHO. - Having said that, I don't want to come across any kind of way, I would like to have a very nice torch lighter one day. I've got a torch now but it's still from the cheap section of the cash register at the local B&M. Seems to keep working so... - I smoke at home. Never a cigar bar or anything like that so I don't have to worry about appearances and what other people think. (I'm not saying that's what people are doing here, just sharing my perspective)