Verizon/LG enV2 plus Zimbra
For those who are interested in using a different mobile email strategy, I offer the following. I tested several phones and wasn't too happy with how they handled Zimbra's mobile web client--largely the fault of Verizon and/or the phones, NOT to be blamed on Zimbra! :D
However, I've just connected an LG enV2 to my Zimbra account and it works quite well. Webmail won't work at all on this phone b/c I've registered my cert with GoDaddy and Verizon doesn't accept their root certs as valid (you can't add root certs-they only accept VeriSign, GTE, Entrust, RSA, & Thawte). But you CAN connect both IMAP and SMTP using their $5/mo email client, and it allows for SSL connections for both IMAP and SMTP so you do not have to go clear-text.
The one wrinkle I've found is that for some reason sent messages don't go to the IMAP "sent" folder; nor have I found a place where they go on the phone either. I worked around this by ticking the "send me a copy" checkbox on the message (which unfortunately can't be set as default), then setting a filter on Zimbra so that if both the "from" and "to" contain my email address, move it to "Sent." This works fine.
I've attached a picture of the email client open to my inbox for anyone who cares. . .