Welcome! Sounds like you've done a lot of research. If you can score a good deal on a pre-19 EcoDiesel, I would roll with it and give it a try and make sure you like it. You could always trade up in a year or two when the 19' EcoDiesels get a litter cheaper.
I ran a 8.1 @ 84MPH in the 1/8th mile. Which would be high 12's... but yea, I still let it cool a few minutes after coming back around the end of the track. I did hot lap it a few times as well, but on a rare occasion.