Berkley's Trilene XL has been a popular monofilament line since first introduced in 1972. Now there's a new and reportedly improved version that won the "best new line" category at the recent ICAST fishing industry trade show. Berkley sent me an 8-pound-test sample spool, which I've been testing to see just how "improved" it really is.
In a nutshell: Yes! The new Trilene XL is indeed better than the old XL. I was pleasantly surprised, especially because I expected more manufacturer's puffery than substance to the new product. It is also approximately the same price ($7.95 suggested retail for a 330-yard filler spool; prices vary because of discounting). Here's what my early testing revealed.
Diameter -- I bought a spool of old-style, 8-pound XL to compare with the new one. Both are labeled 010" in diameter. In measuring each with a micrometer, that was indeed the lines' actual diameter, a plus because many other lines are mislabeled. This also means in comparing the two, that I'm comparing lines of equal diameter--apples to apples, in other words.
Limpness -- The new XL is more supple. I tested this by taking a 6-inch section of each and taping it to the sharp edge of my desk so equal lengths of line were extended into space. The new XL drooped noticeably more than the old XL, which means it's less stiff and will handle more easily. This should perform very well on most midweight spinning reels.
Strength and Knots -- I tested both the old and new XL versions with Trilene Knots (a twice-through-the-eye, 5-turn clinch knot). In most cases, the line broke before the knot did. But the new XL was considerably stronger -- by roughly 10 percent. Tested dry, the knotted old XL broke at about 10 pounds pull. The new XL broke at about 11 pounds, averaged over multiple tests. That 10 percent increase matches Berkley's advertised claim of greater strength.
I have not yet had time to test multiple knots. Berkley claims an overall 20% increase in knot strength, and based on what I've seen so far that might well be true. Nor have I yet had the line on a reel and in the water, but that's coming soon.
You'll be able to tell the difference between old and new because the packaging is different. Old-style Trilene XL comes in a red cardboard box. The new XL version is in a clear pack (330-yard spool) surrounded by a cardboard label.
This all leaves a couple of choices. If you're really devoted to the old XL, you'll probably see widespread sale prices fairly soon as the new version becomes available. Or you can wait a bit until the new version becomes more widely available, which is my plan. The new Trilene XL is truly an excellent product.