I've never owned a double blade guillotine. I usually use a punch, unless I am smoking something thin like a lonsdale in which case I will go with a single blade cutter.
Without a doubt I prefer a Double Blade Guillotine. It always gives a nice clean cut and never have had a problem with the method. I think I am going to pick up a punch one day for obscure sized cigars.
Double guillotine for me. I have been known to use a pocket knife though. I do punch occasionally but I have been smoking more torpedo's/belicoso's lately.
I tend to use a double during the day as that's what is in my car. I like to use the v when I am at home for some crazy reason. I do have a Palio at home but I seem drawn to the v. I just got a lighter with a punch built-in so I am gonna give it a go this week and see what happens!
Palio. when I forget it I use my cheap Credo scissors that work well. I noticed teeth wasn't an option. Never forget that they are there and can be mastered to get the job done. Last resort of course. I did that at a bar the other night because I forgot my cutter.