I've gone through a 2MB Psion 3a, 8MB Revo, 16MB Psion 5, LG Phenom, Ipaq 3630, and am presently using an SL-5500. (maybe move to a C-series if I can ever afford it)
Beside this SL-5500, my Psion 3a has been the love of my PDAs. A cracked screen has caused me to put it aside, as repairing is in the UK and rather expensive. Being able to type was a keeper.
Psion made very stable, useful, and practical handhelds. They were top of the line.
If Psion is thinking of getting back into the handheld market with a Linux based unit, I would highly recommend checking into it, especially if it is cheaper than the C-series Zaurii.