I have a 2007 FX45 w/ 20 inch stock wheels. I have experienced:
Goodyear Eagle RSAs - not recommended. Expensive, hard riding, but very responsive.
Yokohama Avid Envigor - pretty good. Good prices, lighter, better riding than RSAs, at bit more compliant (trading respnosiviness for comfort).
Michelin Premire LTX - incredible tire. Only about 10k on these so far. Again, not as responsive as the RSAs, but their ride and handling are incredible. Quiet. I'd recommend these.