I've got both, trainers and rollers.
I love my rollers far far more.
With my trainers, I focus more on strength training. And I can prop up a laptop and watch/stream videos as I ride in place.
But with rollers, I have to focus on balance, cadence, and being smooth. About the only entertainment I can provide myself on rollers is music via earbuds. But riding on rollers does something more than what trainers can do, and that is smoothness on the road. After my first winter with rollers and back onto the roads, I can easily tell I spent less energy balancing myself and my cadence was higher and smoother. This has translated to at least 1/2mph faster and I feel less tired on longer runs.
It's hard to explain, but I feel rollers gives better results.