2005 Other Toyota Models Intermittent hard starting

I have a Scion XB. Out of the blue I began having hard start problems. By that I mean that I went from 4 or 5 revolutions to start to 6 or 7 seconds. There have never been any codes current or pending. It has always run flawlessly, and maintained meticulously.
I have done the following or the following conditions exist: battery is always fine, engine turns over the same whether it starts fine or doesn't. If I suspect a problem and turn off and try to restart, it starts fine the second time. I have, out of sheer frustration, changed the cam and crank position sensors, cleaned the MAF sensor with the proper cleaner, swapped the c/opn relay, efi relay, and checked the start relay contacts and operation. I have re-seated the four ecu plugs. I have replaced the fuel pump, fuel pressure regulator and filters. I even changed the plugs and insulated the metal fuel line which runs beside the block, even though this problem happens as much cold as hot.
Should I consider getting a fuel pressure gauge or another ecu(used, but warrantied) from Ebay. I'm just about to pull out my hair, but I haven't that much to spare.
I will most certainly pay for the proper advice. Thanks.