I agree that you get SOME experience, but watching what the other guy does...but really, nothing worth paying a full flight hour for. In the end you are paying half the price of the airplane to just sit there and watch the other guy do his thing
Try it over Los Angeles then, and see how long you survive while watching the other guy do his thing
$16,000 for a Seneca II is about right, though remember you should negotiate a good block rate. Should be able to knock at least $2000 off that rate if you offer them $14,000 on the table.
Saw on eBay yesterday, some dude with a twin (can't remember what though, seemed ok) offering a block of 100hrs with instructor. Bid was at about $8000.
Cyer
EA