Evenflo Generations - Raceway carseat is the best I have seen on the market to date.  It has the versatility of a booster seat with the safety & support of a regular carseat.  I would highly recommend to all safety conscious parents/grandparents.  We have had to move this seat repeatedly between cars as my daughter & granddaughter live with us.  It is very simple to secure in any car time after time.  I like it so much that I am thinking of purchasing a second one to keep permanently in my car.