Is Autoglym Interior Shampoo worth it? Yes — it earns a 93/100 CGR Score for removing set-in stains that other interior cleaners leave behind. We tested it on a three-month-old coffee stain in our 2018 VW Atlas that had survived three other products. Using a drill brush and wet/dry vac, Autoglym pulled it out completely. We then cleaned carpets, floor mats, and plastic door panels without switching products. The 500ml bottle dilutes 20:1, so we've detailed two full interiors and barely used half. The only downside: strong chemical smell for about an hour. If you have fabric seats or kids, this is the interior shampoo to buy.