The Sony Ericsson T608
This phone (the
only CDMA phone SE ever made) was the absolute worst. It locked up constantly and had so much lag that when typing text messages in T9, it would display letters I typed 4 letters ago. Also there weren't many shortcut keys on it and you could only search for a contacts by the first letter of their name. To do anything required 3+ joystick clicks.
I hated this phone! It eventually died and I switched to Cingular and got the Audiovox SMT5600.