Check out the new JBL L 100 Classics, if you listen to a lot of rock.
i used to own the Super HL5, and they never did it for me in the rock dept.
If it is the Super HL5 non-Plus then I would agree that it is not very good with rock. The Super HL5 Plus is a different animal which plays considerably cleaner in the bass than the non-Plus with a more coherent and smoother sound owing much to the improved integration between drivers. The bass of the Plus is significantly tauter and tighter than the excessive bloated bass on the non-Plus.
The Super HL5+ is a great speaker. Very natural sounding speaker. They are driven by Naim amplification (NAC 282, Hicap DR and NAP 250 DR).