A sub controller (like the Velodyne SMS-1 that I use) will help get seamless integration of the Maggies and your sub -IMHO, critical for optimizing the kind of set-up you're contemplating. (You'll get room corrected bass out of the deal, too.) There are other models out there that some prefer, but the SMS works well at a reasonable price, app. $400. Once a seamless match is acheived, your sub+main speaker system will be a full range monster that represents ridiculous value for any type of music. Maybe rock isn't the particular strength, but I don't know what will rock better - and offer all the other strengths that this set-up offers - for $1K plus your sub.
Marty
BTW, all the comments on amps and power requirements are on the money.
Marty
BTW, all the comments on amps and power requirements are on the money.