expansion jacket etc -v- bluetooth phone

I have just ordered an HP 5550 with the expansion jacket, card, etc with a view to insert my newly GPRS activated sim card that used to be in my mobile to gain best connectivity - or so I am told. I am a complete novice with this type of system - I just need to access client websites before I meet with them (perhaps whilst in the street outside their building)and send and receive emails throughout the day. I thought I had got this right - but now colleagues are saying all I needed was to upgrade my mobile to bluetooth and forget the expansion jacket etc. Which is best? Any ideas?

[Stevie]

Both do the same job tbh. I personally use my Bluetooth phone to connect to the internet via my PDA. The GPRS jacket basically removes the phone from picture.

Thanks Stevie. The equipment has not yet arrived - when it does I'll try both variants.

Regards

Ed