hi
all the engines are very good as long as there looked after
the 4.2's V8's are very smooth, I have the S-type R and the engine is amazing, so smooth and can be driven very lazy and effortless, you can barely tell when it changes gear
if your after a manual, thens its a 3.0 as the 4.2 is only auto, but I think if you want altimate cruiser, then it auto, they drive so much nicer
cheers
Joe