Oh Jeff, to answer you question regarding PSD availability, the opposite is happening ! Their value is increasing and they're harder and harder to find. All of the PSDs found on AutoTrader I've called about have already sold, I can't find anything I'd be willing to own.
That's in part why I'm asking about the V10 gassers, I've seen a number for sale, and for substantially less than the PSDs. The one response here, noting 10mpg, appears to be typical, which means the running costs will be far higher than a PSD. But when truck A with a V10 lists at $12k, and the identical truck with a PSD lists at $17k, that $5k buys an awful lot of regular gas (and spark plugs, and wires, yada yada).
But PSDs are _so_ relaxing to drive, Katy's biggest complaint is the engine lulls her to sleep