Here's the deal:
My cousin works at an ATT authorised dealer, and long story short, he gets free old phones all the time. I have been offered the option between the LG myTouch 4G (LGE739) or the HTC Desire Z (HTC G2).
For the most part, battery, software support, and features are pretty much the same, except for two major differences.
The E739 has a Snapdragon S2 running at 1000 mhz, whereas the Desire's Snapdragon S2 runs at 800 mhz. Likewise the max stable OC's are 1400 and 1700 mhz respectively.
The Desire is a sliding phone with a physical QWERTY keyboard.
I would like to do a lot of work on my phone, but I can't decide between responsiveness and typing here. Each are of equal importance to me, but I am unsure of just how much an effect the 200 mhz loss will have on my phone and whether or not it's worth the keyboard. I have not yet used a portable device with a physical keyboard.