between the 06-09 the rsx has a nicer body and is alittle lighter then the civic so better mpg. the only thing is i would get an 04 rsx as it is the same but the headlights are alot nicer they have that little bubble to them that causes them to push down into the bumper kinda like the new...
it really depends on what you like more i had bought a civic that was in 2 accidents prior to my buying it. it was at 83,000 miles. i have had it for a while now im actually reaching about 203,000 miles on it and i have not had any major problems with it. the only thing wrong is about 15,000...