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In general when using unknown substances, apply a bit of the stuff to a surface that won't absorb it and see how long it takes to evaporate. Or flush it out with alcohol and wait a few hours for the alcohol to evaporate.
Never use unknown stuff from a company that doesn't even understand its own products when cheaper alcohol will work just as well. Arctic Silver just wants people to worry so it can create a dependence on its overpriced products.
Are you kidding? Their prices aren't out of leauge with other moderate to good performance thermal pastes. There may be more fashionable or debatabley "better" thermal interface materials available... But Artic Silver was a pioneer in the early 2000's and it literally took years for others to catch up, and also produce pastes that don't just perform well but also stand the test of time (pump out used to be a big issue).
Colin and Nevin both work for Artic Silver, and are members in good standing here. If you don't like the products that is your right, but you really don't have any grounds to attack the ethics of the company.
As for Artic Clean, if you haven't tested it, I have tested it on various stock "gum" adhesive when its melted onto a heatsink/cpu, and it works better than plain old alcohol. Sure, you could save the money and use alcohol which works well enough, and I'd even recommend that for regular aftermarket paste... But the gummy stuff is a pain, and the Artic Clean is helpful making it a bit less painful.
As for AS products in general being overpriced, I would disagree compared to other products - it seems competitive, not the cheapest, not the most expensive... With well tested history of long term performance.
Also, don't trust any results you read from a site testing dozens of thermal pastes. Nearly without exception, their methods don't have the resolution necessary to test with the level of precision necessary when mosts pastes on the market perform within <3C (It's been shown that even toothpaste works pretty well, though doesn't last)
