The PP kb thumb typing ergonomics seem fine to me, easy better than a N900 but I could 4-6x finger peck, no touch typing though, but I have very large hands and thick fingers. The key switches are as good as could be expected for membrane and silicone cup, certainly not cherry MX blues but better than any laptop I have owned in the last 15 years. I am just having issues with Mobian right now where the window manager runs slow and crashes with the KB snapped on. I would also prefer a slider but the clamshell also has a large 2nd battery and room to add I2c stuff inside.
Once I can get the kb working in Mobian I will be back in my pocket Linux with hardware keyboard situation I have had since about y2k with my first Sharp Zaurus SL-5500.