After purchasing my Treo 180 on Ebay about six months ago, I've used it as a PDA and phone every day, including when in France, when it was the only computer on the trip. Unfortunately there are some constant worries or problems with it:

• The flip feels fragile: whenever I use the flip there's a nagging worry that rough handling will cause it to snap off. The worry seems justified from reading reports around the 'net. I'm not rough with things - it just doesn't feel solid. My only other flip phone was a Motorola v. and that seemed perfectly solid.
• The sound quality is poor: using the phone held to my head in the normal way results in really bad audio when compared to my old Nokia 6210. Using a headset is a big improvement, but it's still not great.
• Loss of signal: it's always the case that a phone will lose signal sometime. Nokia phones seem quite good at holding on to a weak signal, but perhaps more importantly they re-acquire a signal without any effort on my part. This often didn't seem to be the case with the Treo. The car park at my office is (just) underground, meaning that I'd often lose signal when arriving. There were just too many times when, three hours later, I'd notice that the phone didn't have a connection to the network and simply read "SOS calls only".

On the positive side, the Palm part works really well. Having my calendar and address book with me at all times was a great bonus. When I went back to my 6210 for a few days I really missed being able to look up my appointments with ease. The integration of the various telephone number stores (address book, SMS details, call records, ...) is poor, but I could survive it. iSync worked well.

In the end I decided to upgrade. It would have been nice to get a Nokia 6600, or even a 3650, but that wasn't possible with the Vodafone corporate contract that I'm on, so I ended up with a SonyEricsson t610. The phone itself works well, voice quality is good and no problems with network connectivity. A SonyEricsson bluetooth headset works and is convenient in the car (no need to take the phone out of my pocket to make or receive calls). iSync "just works" after adding a Bluetooth USB dongle to my Powerbook.

Everything isn't perfect though:

• MMS and email don't seem to work for me. This probably just involves a call to the Vodafone support line to sort things out.
• Vodafone use their own icons for the main menu. This is stupid - SonyEricsson presumably spent a bunch of money paying someone to design nice icons that worked well at the necessary resolution. The Vodafone ones are horrible and look particularly poor. Reading around it seems that only replacing the firmware with a "standard" version would fix this.
• Vodafone took over the right hand menu button to take you straight to Vodafone Live! - a function that is already available through a button on the side of the phone. This also means that the interface is different to, say, an Orange t610 (which my wife has). See above about fixing this.
• The quality of the pictures from the camera is quite poor. They are fine for using on the camera, but on the Mac they're horrible.

Overall it's a worthwhile upgrade and, if the firmware stuff could be fixed, it would be much better. Bluetooth is better than I expected and has me wondering about buying a Palm Tungsten.