I got the Treo 600 as soon as it was released and as usual, when you rush into a purchase you end up paying nearly twice the cost.
The Treo 600 is probably better than most PDA’s but it certainly is not the best. My unit frequently locks up, and sometimes outgoing and incoming calls are not retained in the display. I have tried to clear the call register and start all over but I still have problems.
I have upgraded the software but did not see any great improvement in the performance. In fact, there is now an annoying feature. Everytime you update the phone, as in contacts or appointments, the phone has to be reset after the data transfer.
The absence of bluetooth is yet another great disadvantage. Without this, cordless headphones don’t work and it is impossible to answer call while driving.
I think the 650 is probably an improved version, bluetooth and all. Of course you have to shell out a hefty amount to have the phone upgraded.
Such is life