What exactly are you getting out of the 1080p rip of BSG? Wasn’t the series filmed exclusively using 720p/1080i tech? Was there a remaster in 1080p? Otherwise why bother? Do you get better results doing this instead of letting your tv/blu-ray upscale? (All of these are honest questions, not a challenge)
No worries.
It was broadcast in 720p/1080i as that was/is the cable/satellite limitation. Only the miniseries was
filmed in 720p, while the 4 full seasons were all filmed in 1080p and released that way on Blu Ray later. That's the set I have.
I'd originally ripped the series in 720p as that was all an Apple TV could handle at the time. It wasn't very forward-thinking of me, but I wanted to save disk space and it did take a while before I got a 1080p-capable ATV. It's crazy how much bigger are the ripped files when transcoded to 1080p for an Apple TV than the 720p version.
To your original question though, to be honest, I'm not always seeing a noticeable improvement in the picture quality over my original rip. I think this is down to the intentional graininess I mention above, because that renders the higher resolution moot. It's not always grainy and, where it's not, the picture is gorgeous (e.g. the space battles over the Resurrection Ship and above New Caprica), but that's the exception, not the rule.
At the end of the day, I'm satisfying my OCD about these things and also future-proofing my rips as it will never go above 1080p. 4GB per episode is a bit much though...