I had no idea what to expect when I picked up one of these big salami-like things at the local wholesale/retail meat market. A quick look at the label made me think it was some kind of summer sausage, though with more pork in the mix than usual. But it was a good price and the fie print said it was made by John Morrell & Co (though La Primera brand doesn't appear on the Morrell website.)
Commonly found around here in Hispanic markets, I've heard La Primera referred to as "Puerto Rican salami." While I can't speak to the accuracy of that, I can tell you that the flavor is unique: similar in some ways to a summer sausage and in other ways to Genoa salami, it is distinctly different from either of them.
La Primera is mildly fermented and is loaded with whole peppercorns. We've enjoyed it with cheese, fruit, and crackers, and sliced thinly for sandwiches. It's great stuff, and I wouldn't hesitate to buy it again.