I'm currently using a VIA in my eo and the only complain I have is that it could have given me 15% more of battery life if it was properly configured. I use normally a Pentium 4 at 2.6 GHz at work and a Pentium 4 at 3 GHz at home. And if you have your eo configured in the way I have mine (1 GB or RAM and a 7200 RPM HDD) you wont notice any problem or difference if you use your eo to work with Office and other Browsing relative activities. You probably will have some problems if you are a gamer or if you use applications with extensive graphics.
Thanks to the VIA processor current battery life in the eo is the same that you would see in the Q1 if this one had a Battery 10% smaller. This means that a VIA processor no configured properly performs, from the point of battery life, in the same way than an Intel Celeron at 900 MHz. If the VIA processor in eo UMPCs was configured properly with the processor entering in C3 State, the Battery Life in both devices would be the same even with a 10% smaller Battery installed in the eo.
There are problems in the VIA chip set, yes, they are. VIA needs to work more distributing easy to use graphic filters and drivers. I think that they should spend less money in Propaganda in their site and pay a better software developing team. That could put machines using these chips in better condition to compete with Intel.
So my conclusion is one, for the majority of people, VIA will be good enough for everything that a common person does in a PC beside Games (at this moment)* and with the advantage of a better battery life and a lower price.
* I'm programing in Visual Studio 2005 in an eo with no problems at all. Is that considered normal use?