The Kicker kxma400/4 is actually 50w RMS @ 4 ohm and 100w RMS @ 2 ohm.

A 5 chnl hybrid is a mono woofer amp, just in along side a full range 4 chnl.

You could kxma400.2 for the in boats and a mono. That's 100w RMS to each speaker. Downside is no fade.