The best way to listen to two 4g subs?

[Shannon]

To be specific, 5G base format is 9.2 times more information dense than 4G base format. That is one of the few metrics by which we can reasonably measure power easily, so it can be said that 5G format is at least 9.2 times more powerful than 4G. That said, a lot of what gives 5G format it's power is that it supports a lot of extensions and enabling technologies that 4G cannot. The end result is that 9.2 times more powerful is a vast underestimation once you consider those extensions and enabling technologies.

Those two 4Gs you're looking to use are fine together, but use the in the recommended block A - Rest - Block B format. Don't just go A - B - A - B because that tends to constantly drag your mind in different directions instead of allowing the neurons to really become entrenched with the new neural pathways.