Not to put too fine a point on it, but the DTA is designed for 90 year olds with ancient 25" console TVs and no video recorder whatsoever. It isn't really intended for use with flat screen HDTVs and is pretty much worthless for DVD recording. The only reason cable companies even bother offering it is to make a hollow gesture of "compliance" with weak regulations that force them not to arbitrarily cut off "no-box" basic cable subscribers when they switch to all-digital all-encrypted service. Since digital-only channels require a decoder box to play on older glass TVs, offering this near-useless DTA for "free" for a year or two gets the cablecos off the hook cheaply regarding customers with old TVs.
Basically, its a Trojan Horse: the regulations are toothless, cablecos realized they can now force a decoder box fee down your throat even if you're on a regulated "boxless" plan, and thats that. You WILL pay for a box rental one way or another, either 99 cents to $1.99 for the worthless DTA, or $3.99 to $6.99 for the "full-service" box. If you have any plans to use a DVD recorder, you need the full-service box: that is the only option that lets you customize the channel lineup, connect properly to a recorder for a decent picture and stereo sound, and (usually with TWC) set 8 timer events on different channels you can sync with your DVD recorder timer. Depending how many shows and movies you follow to record, the full-service box justifies its cost with one feature: free on-demand. This lets you pull up many popular TV series episodes (and some movies) for free, at any time, in case you messed up your timers or otherwise missed something and need to catch up. If you walk in the door ten minutes late into your favorite network show, you can also press a button to have the show start again from the beginning (if you press the button before the show ends). At least they throw you that convenience carrot in exchange for the forced box.