I now have some funds to upgrade my system, i think possibly my other components deserve a bigger amp, especially the speakers, I have had a few nice budget amps in the past , the rotel being the best and most involving of them all, but feel worried when i push the volume a bit of it running out of steam although it still sounds in control, would i notice a big improvment in sound with something like the creek 50a which is about double the price of the rotel or would it be a subtle change , tone controls are a must, the marantz pm8001 seems to be a good alternative, isnt kef amd marantz a good match?