The Toughpad is tough. But, if all I wanted was a tough pad, I'd buy a cheap $100 Newegg sale tablet and make a styrofoam/waterproof cover for it. Thing is, I also want the solar panel, GPS, radio, weather sensors, e-ink, and other all-in-one gadgetry that will save me pack weight and space. For my needs, if I could have only either a Toughpad or Earl, I'd choose the Earl. Or maybe the Toughpad, which I'd sell, and use the money to buy an Earl and some new outdoor gear.
Processors are getting faster and using less power. There's no reason a CPU upgrade must compromise battery life - an upgrade may even improve it. Except for the issue of development. Redesigning Earl once again to use a newer processor will take time and money. I imagine that at this point, the Earl is costing more to develop than what the project has raised in funds. Yes, Earl is getting behind-the-times in basic specs, and I'm not happy about that, but I think we are still getting more than we paid for (after all, if we're comparing something we paid $300 for to an $1800 tablet, then that's a damn good value), and a faster CPU is not pragmatic. A bit more memory, I think, is reasonable.