I've used the regular Prolink lube for many years. Tried a number of other chain lubes, but keep returning to Prolink, for it's clean-running, and effective lubrication.
The one issue with regular prolink is it's tendency to wash off in wet conditions. Here in Oregon, that's a problem. Progold Xtreme largely solves that issue. I've used Xtreme on a number of wet, gritty, gravel rides, and it does indeed remain on the chain, and does not attract dirt. Yah! When applying Xtreme, it seems just a bit more viscus than the regular Prolink lube, but it's ability to remain on the chain in wet conditions is far better. Xtreme doesn't appear to attract much more dirt than regular Prolink. There are other wet lubes that will last far longer than even Xtreme, but these heavy, sticky lubes attract dirt, and your drivetrain quickly becomes a mess, so I don't use them.
Important tips be sure to shake the bottle well before applying Xtreme, and don't use too much, just one drop per link, no more, then let it dry for at least several hours before riding. Western Bike Works has about the best price on this lube, that I've seen.
i have used the regular prolink for years and it works great in dry conditions but does not last long in wet conditions. the xtreme is not noticeably thicker coming out of the bottle but definitely last longer in wet conditions, about 2 to 3 times longer for me. since it is still a thin bodied lube does not attract much dirt unlike some of the thicker bodied lubes i have used for wet weather riding in the past. i would recommend this to anyone who likes a thin bodied lube that can perform in wet conditions.
I store the commute bike outside (balcony) so the chain loses lube over time. That and the fact that I am commuting in weather -although typically not in pouring rain. I have gradually moved from dry lube, to ProGold, and now to the 'Xtreme' product. It keeps working longer. Put it on liberally, wipe thoroughly, then let it sit overnight before you ride.
ProGold ProLink is my go-to chain lube, and it generally does fine in light rain. The ProGold Xtreme holds up much better in heavier rain and, like the lighter weight variety, doesn't gum up your drivetrain. The Xtreme does a great job preventing corrosion, which is a boon for bike commuters who don't have time to dry off and re-lube their chains after every wet ride to work...This is one of those rare products that sets the bar high and lives up to its promise.
Just discovered this product that has all the qualities of 'regular' Pro-Link with more durability. Impreceptible viscosity increase and I am getting 200 New England winter road miles in JanyFeb per application. Road chemicals, slush, and grime make little impact and the product stays on the chain! And as with 'regular' Pro-Link, cleanup is a quick wipe, dry, re-lube.