Seems like I'm in the minority here, but I side with the SI Impact. I have two X32's at my church that both have had issues that have had to be sent in to be fixed, bad buttons, bad faders, etc within the first 3 years of owning both. Not encouraging when the consoles don't travel anywhere, they are installed in one spot. The SI Impact gives more bang for the buck, more input and output capability, and IMO better sound quality. I've installed several SI range consoles since they came out, and haven't had one go down or needing service.
As far as user friendly, they both have their quirks. I find the SI requires less button presses for some common things...like getting to monitor mixes. Patching on the SI can get very deep, but doesn't have to be complicated. I don't like patching on the X32. Assuming volunteers aren't patching inputs every week, learning the workflow of each is about the same.