Rating: Trust It!
I've historically been a yoga dabbler, intermittently downward dogging with Rodney Yee at home or experiencing short-lived bursts of infatuation with a local instructor. At some point circa 2006 I purchased a lime green Drishti mat. It's made of earth-friendly PVC that doesn't release bad stuff into the environment, and it's thick (good for my sensitive knees), but not squishy (good for balance). It wasn't cheap, but I was in a throes of one of my yoga affairs and wanted a quality mat.
Now I'm really glad I splurged. I've been in a solid, committed relationship with yoga instructor extraordinaire Wini Linguvic for two years, and I'm still using that same Drishti mat. It has literally zero evidence of wear and tear after seven years of use. The company's current version of my mat is the Manduka Black Mat Pro, which costs $100 (or you can find more colors on Amazon). The company claims it will last 100 years. Here's hoping I'll be seeing Wini for that long and can report back.