I'm not arguning the validity of the tests, I only asking why there is no recent test on newer materials and why are some mfg's left out? When you are considering purchasing a new piece of audio equipment, do you rely on two year old data or new data? It does not make sense that low temps over time equal high temps in a flash. Why not have performed the heat / weight test at the same time?
These are all reasonable questions. I am working on an updated and expanded version, but it is difficult to find the time. I am actually quite close. There will be more products in the new version, but since in almost every case I have had to purchase samples to test myself some will still be missing. This is purely a hobby and you can't imagine how much time gets chewed up just doing these rudimentary tests and writing them up. I also get several questions each day and I do my best to answer them all.
The heat tests really started as a way to tell asphalt from butyl. When I first started with SDS, there was a lot of confusion in the market - much of it intentionally generated by the sellers of asphalt products. Asphalt melts at 180°F. While it is tough to get the air inside a car to that temperature, it isn't all that tough to get the sheet metal, where the deadener is actually mounted, that hot. For most applications, a deadener that will survive my tests at 230°F and above should be fine. An interesting characteristic of butyl is that the higher the quality, the higher the heat tolerance. Coincidentally, the higher the quality, the better it functions as a vibration damper. High temperature testing is an indirect way to determine product effectiveness. As an added benefit, heat testing is exactly what the manufacturers do to test the long term stability of the product.
Similarly, manufacturers do hang weights off of the material to test adhesive strength. It is the only reasonable way to test and compare adhesive bond strength. It's also interesting to note that the better the butyl, the more its bond strength increases over time - relative to the initial bond strength. These tests provide useful information and will be in the new version.
So what's changed since the last version? I've tested Cascade VB-Max and it is excellent. I've tested Hushmat and the adhesive is very good but the foil is thinner than I'd like to see in a premium brand. A new Internet brand called Sound Destroyer has appeared. It claims to be butyl but it is asphalt.
Not much has changed among the products I tested.. Elemental Designs finally moved away form asphalt to butyl (my battles with them are almost legendary //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif). Unfortunately, they also moved from an aluminum foil facing to a lightweight plastic that is MUCH less effective and should be avoided. Their new v1² is the first butyl mat I have ever seen that failed in use. Adhesive bond tests show a very weak adhesive and the plastic facing has a very strong inherent curl that seems to cause the stuff to peel itself off when it gets hot.
That's pretty much all that has changed. I'll be covering liquids in the next version. One of the reasons I haven't busted a gut getting the new one out is that it just isn't as urgent as it used to be. People know the difference between asphalt and butyl (at least they know that they want butyl). There just aren't that many FatMat vs Dynamat Xtreme threads popping up. It's a testament to the maturity of the market that the good players I identified in the last version are still around.
tinomen I've just looked at your other posts since you signed up yesterday and it looks to me like you are the Cascade rep who has been making the rounds. You should be pleased with my post above, but it is considered really poor form for a sales rep to masquerade as an unaffiliated user while giving "unbiased" advice. You will do much better being straight forward and identifying yourself - that way people will be able to place your advice in context and will know to contact you when they have CAE related questions.