Well, the good thing I've learned here is that they don't typically last more than 1-2 years in general. Which is not a good thing, of course, but it tells me that I'm not misusing my tools since the shears last approximately that long for me as well.
I have the Malco Turboshear and it's served me extremely well. 4 years and it's still going. Love that thing, especially when you need to cut out a return on the side of a furnace. Just pop a 1/2" hole and cut it out. Awesome. Best sheetmetal cutting investment I've ever made.
I am suspecting a slacker apprentice used my snips to cut copper wire, which might be what suddenly killed them. But I can't say for certain, they were 2 year old snips.
Thanks for the recommendations. I've always used Midwest and Wiss snips, and since nobody has cited using their tools for over 2 years, I'd have to agree they are good ones. I just hoped for better!