[bedoig]

You could try putting you're phone into EVDO Only mode (Start--Settings--Phone--Services--Mode of Operation--Get Settings). I think that will force it to stay on EVDO, but on the downside you won't receive any voice calls while it is enabled (that's my understanding anyway, haven't played with it).

On my phone I had to change the following reg entry to get Mode of Operation to show up in my phone settings:

HKLM\Software\OEM\PhoneSetting\HiddenModeOperation Page

Change the value from "1" (hidden) to "0" (not hidden).

Edit: If anyone knows a way to get the phone to more actively try to reestablish an EVDO connection after dropping to 1X, I'd also like to hear about it.