i'm looking to build a bicycle trailer system with a pair of proel flash8 96dB 8" two ways to start, then add a pair of high efficiency 12s in a sealed car box and eventually another pair of 12s. i plan on using a pair of 12v 7a batteries in series for a 24v 7a system crossed over at 70Hz with inline passive crossovers using sure electronics modules. what i'm wondering about is the best way to wire/amp the subs for efficiency & without stressing the amps. my first impulse was to use a pair of 2x100w modules (originally i planned on biamping to a pair of larger air motion tweeters, but i scored the proels for just $100, and i can roll immediately with them). right now, i'm thinking of getting a more cost effective 4x100w module, but worry that would put more strain on the amp, & think 2x100w mains and 1x200w sub is the way to go. running the subs in stereo would be a waste of power, wouldn't it as per the +3dB rule of "free power" when doubling speakers on a single amp channel. right? finally, wouldn't it be best to load the subs at 8 ohms for an easier load on the amp? sure amps put more power out at 4 ohms, but especially pushing the amps to max power, wouldn't 8 ohms better protect the amp(s)? the woofers i'm looking at are 8 ohms, so they'd be 4 ohms as a pair to start. the 4 ohm versions roll off about 10Hz higher and are slightly less efficient. basically, i'm asking if 2x100 @ 8 ohms + 1x200 @ 8 ohms is the optimum way to go, especially using smaller batteries. my basic understanding of loads and efficiency tell me that's the way to go. many thanks in advance for a more tech saavy evaluation of my plan