We have had very good experiences with VAC, we bought a lot of N54 stuff from them with excellent service. Tony the owner went above, and beyond to get Tony the first Samsona's in the country for the N54 and went to bat HARD for them to get him the proper input shaft, etc, etc to make it as plug, and play as possible. Couple that with the first to have the Schrick cams, they almost always have N54 pistons, and rods in stock, rod bearings, etc. People in the know do not hate on VAC.
With that said, I personally would not want a cap with sensor ports in it, its already messy enough to pull the cap without having to possibly remove lines, and fittings from it so you can remove it. Its a novel idea, but seems inconvenient for someone who works on their N54's as much as we do.
Chris