Although I have never used a pelican case for firearms, I have used them extensively for work. They are virtually indestructible, and I don't see why they wouldn't work just fine with the proper padding. You can make cutouts to fit the individual guns, and some pelican models can be padlocked for security.
We carry a lot of glass and instruments in ours and they do fine. Ours take a serious beating as well!
Hope this helps somewhat in your decision making process.