It depends on what you would like from it. The Eee feels more... I don't know - chuckable? Like a book compared to a brick, if that makes sense. The FlipStart is far from fragile, it's a very strong little device indeed, but it's not something you'd toss onto a couch.
The 220dpi screen is very sharp, very precise, and delivers enough pixel real estate for most webpages and dialog boxes. It also has a very intuitive zoom function - mouse over a window, hit zoom - the window is expanded, and you can scroll or change zoom amount using the jog wheel.
The InfoPane only works with Office 2003 and is a little limited but does do what it claims to - standby the machine with the right settings and available connectivity, and it will wake, check email, sync the infopane, then sleep again - allowing you to read the emails on the smaller external display.
Some people might focus on the solid/thick construction. It's ironic that the Series 5 is held as an example here - the FlipStart has Psion DNA, visible to the end user as certain fonts and approaches in design and the spaced-out thumboard. Particularly familiar is the 'cupped hands, type with thumbs' feel of it - very similar (although with a lot more bulk) to the Series 3.
Performance is adequate; faster (by some margin) than the OQO Model 2 that I tested, much faster than the Ubiquio 711 (but it's a different class of device to that lump). The HD is 5mm 1.8" CE-ATA from memory; an iPod 80GB model from Toshiba may fit to upgrade it if they release them for sale to end users/builders. RAM is not upgradable; under XP I found this not an issue. It even handled playing Warcraft on it, though I used it mostly for LightRoom (at which it was quite useful, though slow on larger files due to the RAM limitations).
It does fit my jeans pocket with the slimline (optional and short-lived) battery. It is much smaller than an Eee! I had a picture of it beside my XPS M2010, which demonstrated two extremes of Windows laptops nicely...
For £350 it's a bargain, though I don't expect Blazepoint to be updating their pricing in any big rush.