While the idea of having separate units for each amp is appealing, I'd have a hard time believing a switch from a B&K, albeit a multi-channel amp, to the Outlaw monoblocks would be upgrade. Keep in mind, this is coming from an Outlaw 755 200x5 owner.
Don't get me wrong, I think Outlaw makes a tremendous product for the price, but it would take some serious critical listening to determine whether the monoblocks would be a better choice.
Just my 2¢...