Regarding the RNAV-C to Williamsburg/Jamestown - There are only two approaches - A VOR-B and this RNAV-C. In terms of usefulness, if it weren't for the RNAV-C, I wouldn't have been able to descend through the thick-ish layer, land and enjoy a great lunch with a friend and fellow PoA enthusiast.
ATC first asked if I wanted the visual. I said.... um... ok let's try. He descended me to 3000', but was still in solid IMC. He said, "Airport is 10 miles, 12 o'clock..." Said.. "ok... um still in solid IMC." So he descends me to 2000'.. five miles later ATC says, "Airport five miles ahead 12 o'clock." me - "Sorry, still in solid IMC no ground contact."
He asks, "Ok, want to try the RNAV-C?" me - "Lesssssdoit."
It was a pretty fun approach. Solid IMC at the IF, the FAF and then down to 1300' where I broke out.