I have C-Springs with all isos right now on a 17 inch rim with 255-40 tire. Thinking about getting Sportlines and using no isos. What is your opinion. I get them cheap. I like the look of a lowered car and just want others opinions.

sportlines are CRAP!!!
they ride terrible and you will drag everywhere you go. you should look into the H&R super sport springs. they are really low and have a better ride quality.
i swapped my sportlines for some H&R race springs and changed to Tokico shocks/struts and the ride is incredible
Most people will agree that The Sportlines Right better than the H&Rs due to a Lower spring rate.
....Go with the sportlines....I <3 mine
I guess Im getting old, but driving around town on m H&R's kills my back....