I've used Break Free CLP for over 20 years and have never noted an offensive smell about it. The organization I retired from owned 6,500 auto pistols, the same number of pump shotguns, and a thousand or so AR's and required that Break Free CLP was the only product that could be used on any Departmental firearm. I've sat in rooms with dozens of pistols being cleaned at the same time and there was no bad odor. I have to argee that there is something other than Break Free at work here and I wish I knew what it was so I could avoid it.
Hoppes is a good product, but don't get the idea that you must use an expensive or exotic solvent to clean a common automatic pistol because it just isn't true. There are a host of solvents that will do a fine job of cleaning your pistol.......common automatic transmission fluid among them........a young friend of mine fresh back from Iraq says he has cleaned many an M2 .50 with it, and I have cleaned some pretty carboned-up auto pistols and AR's with it. Another friend uses ATF mixed with deodorized mineral spirits (paint thinner), and I use a popular homemade product called Ed's Red, a mixture of commonly available ingredients. I even use common GI bore cleaner once in a while, but it's the worst smelling of them all......darn good stuff, though. Especially for three bucks a quart.
I should add that when I've fired my guns quite a bit I don't just wipe them out with solvent-soaked rags because that won't do it. Once they're gunked up good, I do what the competitive shooters do........strip the gun and flood some solvent into the slide and brush away with a toothbrush. Same for the frame and its components. Then I blast them out with non-chlorinated brake parts cleaner (about $2.50 at Walmart). But do this outdoors with good ventilation and wear some glasses and surgical gloves. It will remove all traces of lubrication so you must replace the lube before using the gun again, but the gun will never be cleaner. For a lubricant, I use nothing but Mobil 1 SAE 5W20 synthetic motor oil in my auto pistols and Mobil 1 SAE 0W20 in my AR's.
I now only use Break Free in my skeet gun because it does a good job of keeping plastic wad material from accumulating in the choke tubes.
Big FWIW!
JayPee