I'm used to just about anything that's been packaged in an airtight manner at a lower elevation being puffy. Where you live near sea-level, this would be very different. (I'm at about 3200 feet.)

I'd consider sulfur a bad thing. I have in fact spent time sniffing at various types of meat products, and "good" sausage, in my experience, has the basic "clean meat" smell, with spice. No sulfur.