Oh My Gosh! Are we seeing the passing of the baton to some unknown?
The test was too short by far. I have a fair amount of experience with Slime. I also have a bottle of Ride-On and my riding partner, James, uses Ride-On in his tires. Both products will get tacky as time goes on. When you first put either product in, they are runny, which is understandable. You need to get them inside the tire. If you take the tire off in a couple weeks, you'll find they make a mess. As you get to the end of life for your tire, you'll find they have spread out in the tread area and there's very little to clean or even notice. On my first use of Slime, the mechanic exclaimed "WHAT A MESS!!!" when he took the tire off the rim...but there wasn't any.
As for cleanup...if it is runny like that, the quick and easy way to do it, is simply to step outside and rinse the Slime/Ride-On off with a garden hose. It's water soluble and biodegradable, so you're not polluting anything.
Balancing is a topic for a lot of debate. I think they do help balancing, like balance beads. Detractors will say it redistributes when you hit a bump. Maybe, but how fast does that happen? And how much redistributes? Is it a 30 second redistribution? Or 0.03 seconds? I think it is more towards the fraction of a second and beyond your capability to notice. Whether on a spin balancer or static balancer like they showed in the video, it doesn't work to check balance with any of these products inside the tire. Maybe after 10,000 miles when the substance has turned tacky and stays spread out. But when you've just put it in, the sealant is so liquid, it'll move and the spin or static balancer will get a false reading.
I've had Slime work perfectly on one tire that picked up 4 separate punctures over the 14,000 mile life of the tire. On one occasion, the nail was pretty good sized and air was leaking out quickly when I had the puncture at the 3 o'clock position. I rotated the tire 90 degrees to put the puncture at the bottom of the tire...and the hole sealed up in seconds.
I also had Slime fail miserably once. I had a large roofing nail go in...and right back out...at 60 mph. The tire rotation speed was so fast that the Slime never had a chance and it simply sprayed out inside the wheel well area. That time, the Slime was in the tire already. If I'd had a way to get more Slime to put back in and then rotated the tire to put the puncture at the 6 o'clock position (bottom), I have no doubt it would've sealed just fine.
I hope if this new guy is picking up the baton, that he actually puts some effort into future reviews.
Chris