I am considering the purchase of a P75-C1 but am concerned about some of the lukewarm reviews I've read about the Vizio's scaling engine. These reviews probably won't stop me though, so I'm trying to get some advice in advance about the best way to work with (or around, if necessary) the Vizio's scaling engine when watching cable television.
I have an Xfinity X1 DVR--a third generation Pace, to be precise. Because this STB has no native setting for video resolution (I miss my DCX3400 in this regard), I currently set it to output at 720p--the source resolution Comcast uses the most, now that the company has downscaled and deinterlaced all of its channels to 720p, with the exception of a few local broadcasts. Of the three alternatives below (or any others you can think of), what is the best way to upscale from 720p?
1. Keep the X1 set to 720p (the most "native" setting) and let the Vizio do all of the upscaling? I presume this would be the right choice if, notwithstanding the negative reviews of the Vizio's scaler, it's still better than the one in the X1.
2. Set the X1 to 1080p, and let the X1 do the upscaling? This would be the right choice if the reviews aren't exaggerated--the Vizio really does have a problem upscaling 720p and the X1 would do a better job.
3. Use an external scaler to upscale to 1080p? This is a possible alternative. I have a 5 year-old Elite SC-57 that uses a Marvell QDEO chip. Old now, but decent for its time. But, this alternative would be an improvement only if the Marvell, despite its age, is still a better scaler than the chips in either the X1 or the Vizio. I'm not quite ready to upgrade my AVR yet, because currently no AVR I'm aware of supports Dolby Vision. So, I'm waiting for now.
I'd appreciate any help from those of you who have had success processing Xfinity-sourced video.