Is the ecodiesel responsive on highway?

Hi everyone, I am new to this forum, I presently have a moded 2dr JK Rubi, but unfortunately the JK isn't super baby friendly. I am a huge off road enthusiast, so my choices for a family car was either Land Rover or Jeep. I have owned both in the past, love both brand equally, I really like the new R.R sport, but what sold me on the jeep is the ecodiesel and the new mid-redesign. As I am getting older, I am really getting sensitive on fuel efficiency and right now I feel Jeep has the best game plan. Not to say I like the fact that Diesel in American made.

I have decided to buy an overland ecodiesel with all options except the DVD pkg.
I am really excited about the performances of the diesel from 0 to 50mph, but it feels really "lethargic" passed 60MPH
I don't drive like a maniac, but I do want to know that when I pass an 18wheeler truck with oncoming traffic.

MPH DIESEL V6 V8
30 2.3 2.6 2.2
40 3.9 4.0 3.4
50 5.7 5.4 4.7
60 7.9 7.5 6.5
70 10.9 9.7 8.5
80 14.6 12.5 10.9
100 24.9 20.0 17.5
110 33.9 26.6 22.1

I would love to hear what your experience has been so far.

cheers.