Sushi - to answer your original question, I have the Samsung unit you posted a link for - had it for almost a year. I got it because of price point (it is one of the most attractively priced STBs for just ATSC reception) as I just wanted to stick my toe in the OTA HD water and didn't want to go overboard until I'd had a taste.
The amount of HD content OTA has risen dramatically over the last year, and even if it is not HD, the SD digital picture is far superior to the analog equivalent. As far as the Samsung unit goes, mine has worked without a hitch. It has the reputation of being in the top 2 of tuner sensitivity to lock on to distant stations. As an example, I live in the western foothills of the Sierras about 40 - 50 miles east of Sacramento. I get all of the Sacramento market channels without a hitch, and also get the Bay Area (San Francisco) digitals at night and even sometimes during the day (over 100 miles to the towers). Granted, I have a little antenna height based upon my elevation, but certainly not a clear view to that antenna farm.
At this price point, you get just ATSC and component out (no DVI). It has both coaxial and fiber audio outs, as well as the standard analog. Also has S-Video and composite (but who cares...).
I also have HD from my C Band system via 4DTV and it's associated HD decoder for HBO, Showtime, Discovery, etc. and the PQ is the same for the Samsung. Monday night football is stunning in HD with DD 5.1 sound.
I'd endorse the Samsung just from being a happy user. If you have any specific questions, let me know.
Doug
