Yep, I don't get a speed reading on my trainer either. But it is definitely overall a harder ride. Sometimes, I feel like I can hardly push the pedals. DH and I have the same trainer. One of them feels "easier" and one feels harder. We traded so I got the harder one this year!
I also use the trainer to do specific drills/training. The program I use never has more than about 45 minutes of riding. I couldn't deal with more than that. But, I feel exactly the same as I do when I do a long, hard ride outdoors.