If you can swing it, I would go for the ATI AT1506. It's not actually a Class A amp. It's a Class AB amp. You want as much current capability and resolution for home theater, even if you are not going to use the power. A bigger power supply generally results in a fuller smoother sound (even at low volume levels).
The Lynn is a real lightweight amp at only 56 watts per channel. I suppose if you want a low profile amp, you can get it. But I would rather choose the ATI.
As far as the RBH sub amps, you would need to also find a passive sub-woofer (essentially a subwoofer without a built-in amp). This is not something that is readily available by many manufacturers and may not be as good as other sub-woofers with built-in amps. I don't think this is going to result in something better than your current Paradigm sub-woofer. Plus, these are rated at 200 watts into 4 ohms, which really means it is ONLY a 100 watt amp (into 8 ohms normal specification).
If you want a better subwoofer, start looking at stuff like Rythmik Audio, or even SVS if you have to go low budget.