Go with the 6737i, which is the same phone as the 6757i, but with gigabit ports.
I just got done testing the 6869i and I can tell you that firmware is not ready for primetime. There are still many bugs in the firmware even in the very latest release.
Even worse, there appear to be some really stupid design decisions that make the phone not suitable IMHO:
1. The lowest ringer volume is too loud. The 67xx series can go much lower. This is important for offices that have multiple phones in close proximity and users who don't want to be disrupted by ringing phones.
2. DTMF audio is too loud on both speaker and handset. You have to turn the volume way down to avoid blasting the speaker and then back up to hear the response.
3. Only two line appearances by default. You can re-purpose other buttons to act as line appearances, but then you also have to program those lines with info to match the Global SIP settings. IMHO, a good quality SIP phone should have at least 3 line appearances, and four is even better. The redial and call history buttons should have been softkeys anyways.
4. Lots of firmware bugs- Currently (1) if you repurpose the redial and call history hard buttons as line buttons, the LEDs don't work, (2) If you're pre-dialing a phone number and your registration timer expires on any registration, the pre-dial clears and you have to start dialing again, and there are others...
I really hope that they fix these bugs, as the phone is very nice aesthetically.
The 6757 and 6737i are still the best SIP phones ever made IMHO.