Saturn,
If possible stay away from the WinTV line of tuners. Not very good quality, and even better - stay away from any kind of internal tuning solution as it picks up quite a bit of noise from the PCI bus and other components inside the machine (PSU etc).
However, if your looking at one of those cards for the bundled PVR solutions then you dont have much of a choice.
I went down virtually the same route as you. I picked up a VB50HRTV like you, and the deinterlacing was horrible not to mention the auto-brightness issue (not macrovision as it was doing it on a coax cable source as well). From there I tried virtually every capture card out there, from the WinTV's to Pinnacle's to a Zoltrix card modified by Ken Hotte (cleans up the picture quite a bit actually). I was never satisified with any of them. The ATI's worked, quality was eh, ok but I could not use Dscaler with them at the time (advanced software deinterlacing routines and misc noise filters).
Currently I have a Holo3DGraph (Immersive Inc.) input board (no tuner, input only) which has SDI, component, svideo, and composite inputs, AND does DCDi (Faroudja) deinterlacing. The quality of this board is amazing in terms of input boards for the PC, however it has a price to match and requires external tuning/sources (my case, satellite and dvd player for video sources as software dvd is horrible at video sources).
However, if your on a budget I recommend taking a look at the Xcapture board from Prolink, and or the newer Asus TV card as both are based on the newer Conexant chip CX23* which the H3D uses. Supposedly both are supported by the alpha version of DScaler as well, and some even say that some of the new deinterlacing routines rival that of DCDi, but I can not personally vouch for either of those cards or the new deinterlacing routines as the purpose of purchasing the H3D card was to put an end to all the upgrades and tweaking/frustration etc.
Side note on the H3D board, its a 480i input board only, 480p may be supported in the future, so even though it has component in you shouldnt get your hopes up on the idea of trying to pipe in a 1080i source and deinterlacing and scaling to 1080p or something (PCI bus cant handle it anyhow). But bringing in 480i with DCDi magic and say a Radeon to 720p looks beautiful (I dont like 1080i personally, and there are issues with the overlay and interlaced resolutions with the Catalyst drivers right now)
-pd
