i would personaly go for a 6630, as it is a series 60 symbian smart phone like my current 6260 and old 6600 and ive not had a single problem with either and the 6260 connects painlessly to my X51V.
i know this doesnt exactly answer your question but hopefully should be helpfull.
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"I'll be more enthusiastic about encouraging thinking outside the box when there's evidence of any thinking going on inside it."
- Terry Pratchett
I have been using a 6630 for a year now and love it. Axim connects to internet and MSN throught it no problem and can file exchange over BT both directions with A06
Thanks for your replies, everyone... I had decided on the Nokia but they have sold out so it's not available under the promotion! So now I have to choose either the Sony V600i, or a Samsung Z500... or pay full price for a Nokia! Decisions, decisions...