Great little item for shooting in your vehicle. The Puffin Pad (see web site here: http://www.puffinpad.com) is a nice light weight alternative to using a bean bag to brace while shooting from your car. Plus I like the notch in the bottom that allows to brace it on your Window if you wish to rase it up a bit as well. If you fine yourself shooting from a car often, it just might help to provide a solution to holding that long lens combo.
Till next time, happy shooting!