Every product in 2008 was completely viable which is why the Federal Reserve bought everything.
Only 7% of the borrowers defaulted by then, there wasnt mass irresponsibility on the people with mortgages as suggested, this alone blew up some institutions because they were leveraged nearly 50x and one month of missed mortgage payments would cause a massive drawdown on their portfolio.
Without leverage, a portfolio where 93% is going to pay a lot in interest over 5-30 years is a good portfolio.
So there is no reason to get uncomfortable or anxious by seeing the words “subprime” “CDOs” or more, as it comes down to whether the accounting is done properly and the leverage is low. Which, I believe is being done. The "big crash" always comes from a different and unexpected (or less expected) angle, where some completely different sector has too much leverage and flimsy accounting.