The drag strip is a track of sorts...the autocross course is usually a parking lot...abandoned air field...or just a bunch of unused asphalt/concrete. I competed a bunch in 2000/2001/2002 in autocross....in 2001 alone I did 17 events...X 4 or more runs each event. Its fun..but spending 3/4 of a day or all day long at an autocross for three to four 50 second runs got old after a while.
I'd much rather do a track day with 4-5 twenty-five minute sessions at a road course now.