The difference would be minuscule and not likely to improve your reception. Also, twin lead picks up ingress interference which may make the signal quality worse.
Many people are misled by the so-called "signal strength" numbers displayed by the signal test feature in consumer TV tuners. The number it displays is really an indicator of signal quality, derived largely by how much error correction is taking place. Instances where someone's off-air reception benefits from reducing coax loss by a couple of dB are relatively uncommon, and if one of your off-air signals is so anemic that it might make a difference, you would be better off slightly preamplifying the signal as soon as it comes off the antenna.
Edit. I was unable to read the light green lettring in your signature, but after highlighting it, I see that you have stacked Yagis and a pre-amp. Have you tried posting your situation in AVSForum? Sionce you've already spent some money but not achieved the results you want, you probably should have your reception situation analyzed before you spend any more.