I had a set of Benchmark run in mono configuration. I simply could not get them to sound great in my system and had to sell them.
They had a predominant midrange forward character where the midrange was so much louder than other frequencies. It was clear and dynamic, almost too dynamic. I too have 90db sensitive floorstanders like you and cannot recommend the Benchmarks.
I have an Orchard Audio Starkrimson on order as part of the tour and am looking forward to it.
In the mean time a Parasound a21+ is sounding pretty decent.