Although, I cannot offer much help I can relate to your situation.
The only Sprint phone listed on their website that works with iSync is the PalmOne Treo 650, which probably wouldn't interest you from the sounds of it. It doesn't interest me.
<RANT>
I'm already a current Sprint subscriber and will have Tiger tomorrow. Last time I was in the Sprint store they said they had three models that worked with iSync. Yes, three, I don't know why they don't have all of their offered phones on their website. One was the Treo 650 and the other two I didn't care for the physical design, neither were flip phones which I prefer. iSync works with Motorola v60i/p/s/t/t color, which are nice fiip phones, but of course Sprint only offers the v60v. Why?!?
I don't even care if it is BT or USB to sync, any flip-style phone offered by Sprint that works with iSync will do. Does anyone know of such a "Wonder Phone"? I realize I'm asking for the impossible here.
I don't understand why the iSync phones seem so limited, how hard can it be? You would think each phone manufacturer would have a defined way of communicating with their phones. Why can iSync work with Motorola v60i/p/s/t/t color but not the v60v? I know asking questions like this is rather pointless. I'm just frustrated becuase I've been searching for months. It shouldn't be this difficult to find a phone with your preferred form-factor, the carrier you like and the features you want (iSync compatibility).
I hate the carriers, they limit the use of phones to a ridiculus level. You have to buy ringers through them (I don't, but wish I could copy MIDI's or MP3's to my phone). They are fighting iTunes because they want to deliver all the content and make money. Plus, they are all in bed with certain phone manufaturer's so you can't pick the phone you want and the carrier you want in many cases. On Sprint's website they have 1 Moto phone, 1 Nokia phone and 3 LG phones. All of the rest were Samsung and Sanyo. (I didn't include the Palm and PPC devices in that count). This never bothered me as I really like Samsung phones, but now that I want to use iSync, I just seem to be screwed.
</RANT>
Any suggestions for US carriers that have a nice iSync compatible flip phone? I like Sprint, but I will leave if I cannot get what I want. If no good flip phones, then ANY good phone that is not a Palm/PPC device? I would like to sync my contacts and calendar. To Do items would be nice, but not a requirement for me.
Thanks for any help you can offer.
I am waiting for the K600 personally! 