With a spacer lift the ride will be more rough. A full suspension lift will typically ride like stock if not better (usually better in most peoples mind). A spacer lift is basically stacking a peice of steel or poly on top of your coils front and rear. In the long run this will cause more wear on the coils and other suspension components. A Suspension lift comes with longer coil and also slightly longer shocks and struts to achieve the best ride possible.
2010 JKU - Stock for now
2005 WK - 6" lift, 35" BFG's, a lot more (SOLD)