I have used HP iPaq 6515 with Handimap, Nokia E61 (with external bluetooth GPS) with Smart2Go, and Garmin Nuvi with Garmin Maps. For Navigation the Garmin wins hands down, but then it is a dedicated device for navigation. The Handimap software and Garmin software will give speed trap warnings for static speed traps, the Nokia does not have that information as far as I can tell. The Nokia userinterface is better than Handimap though. The bottom line is that the Nokia maps are good, but don't have the same coverage and detail. Their licensing model is favourable; you can even activate it for just a week or so while travelling, but then the cost per day is comparatively high.
No multipurpose device will beat a dedicated device, but then can one justify the expense of the dedicated device?
I am gettin Handymap Ai Gold 2morrow i hear it has the best coverage in SA and is the best when it comes to searchin for your destination that is SA. It should be so since it is made in SA. I don't trust Garmin since you have 2 pay every year for maps that are not really good. Handymap seems to be the only software with free map updates and a free PC version. If you know any other software that offers the same please tell me!