I've read conflicting reports on how much more powerful it is in practice. I've seen only one direct review that said the Librem is clearly much faster, but I've also seen a few comparisons that show little to no difference in daily use tasks.
The problem might be that we don't have a quality comparison yet (or I haven't found it), but I wonder if there is a performance bottle neck in the hardware. Maybe the software is still better optimized for the pine and the Librem will start to pull ahead as more developers get a chance to work on it.