How to control video steam Kbps/recording quality

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I've used Sage successfully for several years, and have just now switched over to the Hauppauge HD-PVR capture device. I have TimeWarner cable with a Scientific Atlanta 3250HD stb's; my Hauppauge IR device for changing stb channels is working correctly between HD-PVR and stb. (I use MediaInfo for file information, and use MPC Home Cinema to play video files (besides Nero, Sage, and Arcsoft TotalMediaExtreme, TME. For editing, I use VideoRedo v.4, and use multiAVCHD to make AVCHD/Blu-Ray disks.)

In general terms, using the HD-PVR device, nearly everything seems to be working well. My concern/question, however, is about saved-to-disk, video stream Kbps rate: How do I *reliably control* this setting--and any other user-configurable options affecting file quality?

I have two 3250HD stb's; one is used as a conventional stb connected to my living room Panasonic plasma TV; my other 3250HD stb is connected to my HD-PVR device, and computer.

These stb's have settings for: picture size (e.g., stretch), aspect ratio (e.g. 16x9), and output resolution: namely, 480i, 480p, 720p, 1080i. My living room stb box accepts and maintains the setting of "1080i"; however, my computer/HD-PVR-connected stb box, while offering these same four resolution options, refuses to accept a setting of 1080i (or for that matter, of either 480p, or 720p as well). In the stb's Setup, all four resolution options remain "bulleted," even though I have attempted to make a change to some other resolution than 480i, have confirmed that my "tv" can support each of these other resolutions, etc. Is this difference in my ability/inability to adjust output resolution settings in the case of these two respective 3250HD stb's somehow connected to the presence of my HD-PVR in the case of one of these boxes?

I am unclear, however, in any case, just how relevant my making any of the above settings in the stb actually is, insofar as output file quality/specifications is concerned.

In the Arcsoft TME capture program, the user can specify the desired video encoded bit rate (up to 13.5 MB). I set this TME setting to 12 MB.

It seems (am I correct in this?) that I have no control over the input resolution of the programs I receive. For example, I notice both in the case of TME and Sage .TS video files, that different programs have different resolutions: e.g., National GeographicHD channel has some programs in 1920x1080, yet others at 1280x1720; yet various non-HD ordinary movie channels are only 720x480.

In TME I can set the encoding bit rate (e.g., to 12 MB). However, the Sage "Best-H.264" is for 5.9 GB per hour. How do these settings relate; and, is this setting in Sage (of, evidently, "up to" 5.9 GB) adequate for (reasonably) maximal quality? Is there anything else I can adjust/control to maximize recording quality?

I have made test recordings both in TME and in Sage of sequential portions of the same tv program, and yet, if I am correct, the Kbps report from MediaInfo for the TME recording (at a setting of 12MB encoded bit rate) was higher than the "Best-H.264" recording in Sage (for example: TME: "8 256" Kbps; Sage: "4 601" Kbps).

I would appreciate any general education/enlightenment about these issues, with advice especially concerning making Sage video files to be of at least as high quality as that of TME. This is because I generally love the Sage program, am comfortable with its interface, and value its capabilities and efficiencies (conversely, I find the TME program's capabilities very limited and inconvenient, not to mention its dependence on TitanTV, even as WinTV Scheduler/Windows Task Scheduler). Thank you.