Upgrade from Krell KMA 160's to FPB 450's-?

Will there be a significant difference between these two pairs of mono's? I run a Krell KRC-HR pre amp and a pair of Klipsch KLH30's. Also concerned about future repair cost on the KMA's. Opinions from those who have heard both please. Thanks
Don't know what you ended up doing but I would be interested in purchasing your KMA monos if they are available. Thanks