Wow...I'm sorry that you've had such a hard time with Sprint. I've had an account with Sprint for about 10 years now, and I've never experienced poor service like this.
If I were you, I would collect all 3 phones and their packaging...go to the Sprint store and tell the Manager that he/she needs to fix the connectivity issue with the Treo 700p or you're returning all of the phones and cancelling the account. Be nice about it, though. I always get better service when I'm not an arse.
Let us know how things turn out.
P.S.: I mentioned to you, in another thread, that I recently opened a new account with Verizon. I've spoken with their reps (for free, unlike Sprint) several times re: various questions that I've had. And, I even asked for help in performing a hard reset on my 700p. All calls were handled very, very well. It's only been a week or so, but I'm already hooked. I've changed my Sprint account to the bare minimums as I'm still under contract with them.