Upgrade or 2 pairs?

I currently own a pair of Harbeth 30.1's.  I enjoy them quite a bit, but they were most assuredly designed for jazz and classical music.  This is fine except I listen to rock music of all kinds about 50% of the time. 

I've not listened to the 40 series yet, but I'm wondering if they would provide the extra punch I'm seeking while keeping the elements of the 30's I find appealing.

Alternatively, I would not mind having 2 pairs of speakers, keeping the 30's and getting a pair of floorstanders.

So, I'm looking for opinions on the 40's as well as speaker suggestions more suited towards rock music.  My price range would be in the $4-7k range, keeping in mind that I don't mind waiting for a demo or used model, so retail prices up to $12k.

The rest of my system is a Rogue Pharaoh, Oppo BDP 105, VPI Classic 1.