I went with the mini's over the 5's to complement my 11s. I made the right decision.
The mini's keep up with the 11s for surround duty and then some. If I'd gone with the 5s i'd probably just be regretful of the fact that I now have those huge tall rears that probably won't add much to the surround environnment.
Just my 2 cents but mini's tear it up nicely...
As mentioned in the above thread...an SPL meter is a MUST - those mini's/5's/7's/whatever as surrounds will need some tweaking to match the great output of the 11s...made a huge difference in my setup
I've also heard the Mini's (being the Swiss Army knife of Paradigm's line) work well with the Studio series.
Maybe others can verify this, as I have not heard this first hand, but should you choose to upgrade your fronts, it won't create the need to change your rears.
Again though, I haven't heard this myself.. But, it's always nice to be forward thinking in your present purchases.