I ordered a deli slicer last week off Ebay but my order ended up getting canceled. I thought about how big the machine would be, and needing power and the one I'm looking at you have to take apart with an Allen Wrench to clean it. Anywho, I bought a Zakarian by Dash Safe Slice Upright Mandolin, I got it on QVC for $36, Amazon has they for a bit more without the Zakarian branding.
I have a decently nice normal Mandolin which does a terrible job at Pepperoni. I have the small food processor attachment for the Bosch Universal Mixer, which is unusable for Pepperoni. My Breville Sous Chef does a great job usually, but it's bulky, takes a lot of time to get out and get set up and cleaning it is a pain. Can't beat the speed of it actually cutting them, but I normally just slice up 2 sticks so it's just not worth it.
I didn't have high hopes this would work well, but decided to give it a try tonight. Now I've only used it for Pepperoni once, so I can't comment on how it'll hold up for this task. But I was extremely impressed at how well the Roni came out. The thickness is adjustable from .5 to 8mm. And it's a vertical mandolin so it would be just about impossible to slice yourself open while using it. The feed tube's much more narrow than a standard mandolin, but for Pepperoni it's plenty big. I took a Dietz & Watson stick out of the fridge and sliced 1 of the sticks in half, the mandolin cut it like butter. Every slice was even and there were no pieces with torn up edges. For around $40 this thing's been awesome the few times I used it. It's also easy to clean and folds up nice and compact. I don't know how it'll work with other brands of Pepperoni - I plan to buy a Boar's Head stick to test it out next week. But if it works this well with others this is the best method I've found to slice Pepperoni that doesn't cost an arm and a leg and/or take up half a counter.
I really really suck bad at slicing Pepperoni by hand, and where I buy my Dietz & Watson sticks the deli counter won't slice them for me. And that's my favorite Roni for the price so I had to find a way to slice it and with my OCD and limited knife skills doing it by hand would be a no go.
Anyways here are 2 pics, I only took a pic of a single Pepperoni, but they all came out looking the same. It was set to 1mm, I think I'll try .5 when I make pizzas next week so I'll post a few pics.