Pros: Good picture quality. Good reception. Fast tuning time. Analog pass-through. Adequate features.
Cons: Remote control is a bit too directionally sensitive. No S-video output. No audio volume control.
I purchased a Coby DTV-102 digital TV converter box (for $45 at Fry's Electronics) and a Zenith DTT901 (for $50 at Sears) at the same time and brought them home to compare them on the same TV with the same rooftop antenna. Both boxes are eligible for the $40 government coupon. Based on the reviews that I read, the Zenith DTT901 seemed to be the gold standard in terms of reception and picture quality, while the more expensive ($60) Echostar PalTV seemed to be the gold standard for program guide (while still having good reception). The other main choices at my local retailers got bad reviews on critical features. The Apex DT250 ($60 at Target) got bad reviews for its poor reception. And the Magnovox TB110MW9A ($50 at Walmart) got bad reviews for its slow tuning times as you switch from channel to channel. I wondered how the cheaper Coby DTV-102 would stack up, but I couldn't find any reviews, so I thought I'd compare it to the DTT901.
I could not see any difference in the video quality between the Zenith DTT901 and the Coby DTV-102. Both provided very good, crisp pictures. I've worked in the TV set top box and game console engineering industry for many years and I have spent countless hours analyzing the video quality of the boxes that my companies produced, so I think I have a pretty discerning eye for video quality.
I could not find any difference in reception between the Zenith DTT901 and the Coby DTV-102. Both boxes pulled in the same channels--20 channels in my area of Silicon Valley. And both boxes had trouble cleanly pulling in one of those channels without occasionally displaying some "block" noise.
I didn't find any difference in tuning time between the Zenith DTT901 and the Coby DTV-102. I didn't put a stopwatch on them or anything, but both seemed similarly and adequately fast when changing from channel to channel.
Both the Zenith and Coby boxes have analog pass-through (when the boxes are turned off). Although analog broadcast signals are going extinct, analog pass-through is critical if you feed an analog RF output from your living-room's cable/satellite/DVR receiver into your home's cable system (perhaps on channel 3-4 and/or channel 60) so that you can watch satellite/cable/DVR on remote (perhaps bedroom) TV which doesn't have its own cable/satellite/DVR receiver.
Neither box has an S-video output or a smart antenna connector. Otherwise, both boxes have antenna input, RF output, as well as the red, white, & yellow stereo & composite video outputs, and a channel 3-4 switch.
I thought that the Zenith DTT901 had a more user-friendly initial set-up. (But since you only need to set up the box one time, this isn't a big deal for me.) Both boxes were easy enough.
I thought that the Coby required a more direct pointing of the remote control at the box-- which was a little bit annoying. I'm not sure if that's the fault of the remote or the receivers sensor. I suspect the latter.
One nice feature of the Zenith remote was that it has TV-power button that lets you turn on and off your TV. It supports a long list of TV brands and it even worked with my ancient Quasar TV, much to my surprise. The Coby remote control did not have a TV-power button. Since I also need my remote control to control my stereo (volume), I'll end up using a third-party universal remote. But if you don't think you'll use a universal remote, you may find the Zenith's TV power button a very worthwhile feature.
Another nice feature of the Zenith, is that you can control the audio volume of the converter box's audio output with the Zenith's remote control, thereby effectively controlling your listening volume. To use this feature, basically you have to leave the TV's volume turned up pretty high. Then you can then use the Zenith remote to control the volume of the audio signal that the converter box feeds to the TV. Again, that feature isn't important to me because I plan to use a universal remote to control the volume of my TV and the stereo attached to it. But if you don't plan to use a universal remote, you may find Zenith's volume control to be a very worthwhile feature.
Both boxes have a basic guide, showing what's on now and what's on next, along with information about that program.
Both boxes seemed to have almost identical buttons and features for subtitles, language, aspect ratio, etc.
BOTTOM LINE FOR ME:
I don't plan to spend much time watching TV on my old back-bedroom analog TV tube, and I'm sure that I'll replace that tube at some point in the not-too-distant future, so I decided to keep the cheaper Coby, return the Zenith and put the savings towards buying a digital TV. The Zenith was a bit nicer, but it wasn't worth $5 more to me. If you plan to watch a lot of TV through your converter box and you don't plan on using a universal remote control, then it's probably worth spending the extra $5 for the DTT901 for its better remote control functionality.
Personally, if I planned to watch a lot of TV through my converter box, I'd spend $60 for the Echostar PalTV and get the great grid-based, 1-week programming guide with VCR timer.
For a comparison of the features of many of the CECB government coupon eligible converter boxes, check out this link.