I've been using it for around 3 years now and love it. The soap is very good at cleaning road film and it always drys spotless.
Based on the amount of soap required to clean my X5 and the number of spot-free rinses I get out of one filter, I've roughly worked out that it costs me around $1.50 per wash...definitely worth all the time it saves me in not having to wipe dry the vehicle...
