I use a HDTVa and it works great for me here in DFW (75006) and worked great when I was down in Austin. I get everything with the exception of Lo-VHF 3, but it's my understanding it's moving to UHF.
For the record, I don't work for Terk, Audiovox or any manufacturing company for that matter. And I'm not here to recommend the HDTVa to anyone. In fact, I had never heard of the Terk name until May 2009 when a fellow at Stereo East mentioned it in passing to me. I got one at Best Buy and was pleased with it after going through various other indoor antennas branded as Radio Shack, RCA and Phillips.
Because I do a lot of traveling, my affinity for the HDTVa might come from its small size and performance in demanding circumstances. Most recently, I was in the downstairs den of friend's home in the Chicago western suburbs, about 35 miles from the loop (Willis and Hancock are the sites for the majors). In spite of being at ground level, that little Terk managed to pull in all of the full power facilities and one of the MeTV 15 kW facilities. It got WBBM on RF-12 and the simulcast of WLS on RF-7, both of which have been problematical for some in Chicagoland. Unfortunately I didn't have access to the SMART application there or I would have saved the waveform images on the Sencore device. As I recall, they were all very square (as desired for ATSC) but I don't remember the power levels or MER figures.
So to repeat the line from my earlier posting, it ``works for me''. Maybe my magnetic personality just attracts RF! :-)
[...later edited to add...]
Lest it seem that I'm overly pimping the product, I also tried the Terk HDTVa in Washington County, PA (about 20 miles south of Pittsburgh). It only got KDKA (on RF-25) and WTOV (on RF-9) from nearby Steubenville. There really wasn't a trace of anything else. In the rough terrain of the tri-state, an indoor antenna faces some real hurdles.