I've replaced all my glock barrels with LoneWolf barrels. FWIW two other shooters I hang out with have as well. All three of us saw some accuracy increases across the board and consistently over time so barring mass psychosis it was a real improvement. 25 yard groups tightened up quite a bit for me, 15% or so.
The downside, potential, is that the LW barrels are machined with a tighter lockup, this contributes to accuracy but it could have potential in a really dirty gun to create a malfunction. I haven't seen it myself and neither have the other 2 shooters (or my wife but she's a recreational shooter). But it is something to be aware of.
If you're a reloader of .40 the LW barrels have good support and have much less 'bulge' than the glock barrels do, especially the older gens.
I'm not thrilled with the rollmark but I'll take cost and performance over vanity most days.
I've run their barrels on 2 G19's, 1 G17 and also a G22 with a 40 to 9 conversion barrel. Both straight and with an Octane 45 hanging off them with zero problems.
The only change I made on the G22 was to swap the recoil spring out for a 1 lb heavier to compensate for the increased mass for the conversion barrel. Note that it went 2-300 rounds even with my light plinking loads without any problems (115gr over 3gr titegroup), but the springs are practically free so why not? I did not change the extractor from the 40 to the 9. I prefer to be able to quickly change barrels/calibres in the field when I want to swing both ways and a barrel/spring is easy, a barrel/spring/extractor not so much.
Note that you can use G22 mags for 9mm but you'll have the occasional FTF. I really need to mark those better.
If you shoot cast then the LW barrels are standard rifling and can handle it without leading up.