I used a pair of ACI Titan II LE with them. They are not the most current technology,however, the do a very nice job of filling the bottom end. I was considering upgrading to the subs you mention and think either will do a great job. The only way I could decide is put them in my system. Never got that far. I was leaning toward the Rythmic first. If you can afford it, a pair always works best for my ears.
Don