I went from 22's to 60's and moved my 22's to the rear just like you are planning. My decision was based on room size (large with vaulted ceilings and open to other rooms). The 22's sounded great but lacked a bit in the upper bass even when accompanied with a sub. The 60's were a dramatic improvement to my ears both playing with and without a sub. I would be suprised if you were not very pleased with the improvement in sound. And yes they are still amazing at low volumes.
I have come to appreciate this low volume thing since my son was born just 6 months ago and waking him up from a nap would more than put me in the doghouse!
