Two issues:
1. Fox is at various stages of implementing HD.
2. VOOM OTA PQ is no better or worse than most OTA tuners.
I have three (3) OTA tuners, including my single VOOM receiver, two OTA antennas and receive programming from 4 DMAs. I have literally made hundreds of OTA comparisons between the three receivers and have found no discernible differences in PQ. Sure, some OTA receivers are more sensitive and do a better job of locking marginal signals, but once locked all three look virtually identical...be it on my Mits CRT RPTV or Sony LCD RPTV. Oops, almost forgot that I borrowed a friends Samsung SIR-T??? over the summer and noticed no difference in PQ.
The only time I recall having a problems with OTA PQ was during the first few days of 5.xx (only had it for a day or two before being updated to 5.68) and when I had software version 6.10. My hunch is that some of you may have bad equipment or maybe suffering from a shoddy install. When properly installed (and when given working equipment) it has been my experience that the VOOM OTA is no better or worse than my Mits and Sony OTA...both have excellent built-in tuners!
Also, keep in mind that not all DTV is created equal. There are some stations I prefer viewing out of DC, while others I prefer viewing out of Richmond VA or Baltimore. Examples: CBS (WUSA-DT) out of DC started multicasting a 3 Mbps Radar sub-channel over the summer; PQ on their main channel immediately $h1t the bed. After receiving complaints, they allocated only 1.5Mbps to their Radar which [temporarily] solved the problem. Ok, football season kicks-off and I am seeing motion artifacts galore. It's not horrible mind you, but the PQ is nowhere close to where it was last year - it sucks! Therefore, I now watch CBS Sports out of Richmond since they don't multicast.
Until recently, I used to watch ABC out of Baltimore since the DC and Richmond stations couldn't train their operators to throw the HD switch on a consistent basis. However, they recently automated the process and all is well. All three ABC stations are multicasting, but it doesn't appear to have any affect since they are using 720p (less bandwidth).
Currently, all three Fox stations appear to have their own unique set of HD issues depending on where they are in the Fox's HD transition (HD, non-HD, network splicer, no network splicer, etc.). You may wish to check-out the VOOM "In You Area" Forum or visit avsforum.com for more information.