There's a big price range in those digital borescopes: from about $12 to the-sky's-the-limit. I've had a couple of the cheaper ones and they're usually okay for what I use them for. But the images on them aren't great except maybe at one focal length. And while they may work pretty well for something like a .50 cal, they may not work so great in a .32 cal. Part of that has to do with the size of terminal lens (5mm, 6mm, 7mm, 8mm ...) and resulting quality of the image. This is one case where pretty much you do get what you pay for, and expectations should be adjusted accordingly. I think that in some circumstances, some kind of simple bore light (like a fishing bobber thingy or arrow nock) may be better unless you're willing to shell out significantly more bucks.
I would up my game, but I have almost no genuine use for a better one. I did use it, however, to shorten the "cleanout screw" in my Crockett rifle so it no longer protrudes into the patent breech (and then Loctited (excuse the verb form) that screw in). I just ordered some little battery bobber lights from Amazon to see what they'll provide -- mostly out of curiosity. 
