I gotta say, I usually run Texaco gas in the ZJ (one of the cheaper stations around here), and when I swapped intake manifolds a few years ago, I was shocked at how clean the valve stems and ports were. I don't see how SeaFoam could do much better.
That said, I did run Sea Foam through the old girl just for fun, and even at 440,000kms, I didn't get the clouds of smoke I expected after reading about other people's experiences. In addition, I noticed no improvements in the way it ran (runs pretty well except just after a cold start). It was smoky for sure, but not like I expected.
Buy all the products (preferrably on sale!), and report back to us if anything actually makes a difference that someone else might be able to notice!