You can't avoid them but not driving like a w*****r - ie at high speeds up someone's arse will reduce the level and location you get. I tend to keep distance myself and cars in front mainly for this reason, although obviously it's good practice in terms of stopping distance and visibility - if you do want to overtake someone not making progress, it's easier and safer to see what's going on further in front that way too.
The clear films are okay but generally all examples I've seen still get marked by stone chips and will then cost as much as a respray to replace so are not economically a lot of sense (unless you can get the stuff supplied and fitted very cheaply), especially if you do not have a perfect bodywork to place over. I did tend to get a lot on the sides of the car due to country driving, but fitting the GTI flaps reduced the level of these - most that I get are high up on the car from motorway driving now.
I find the worst number of chips are from commuting in the winter - unsure if this is related to grit on the roads, or the ice doing a pretty good job around here of breaking up road surfaces in Jan / early Feb.
