krell ksa-250- vs ksa-200s vs fpb-200

thanks guys, Im running monitor audio gold reference 60s with Audio Research ls16 pre, not the hardest speaker to drive but I like to rock out and want great control with slamming sound at high spl. I mainly listen to alt rock, 80's industrial and classic rock. By ease of use I mean doesnt sound best after being on for 2 hours. I usually leave my amps on 24/7 but doubt I would want to do so with something like the ksa-250 that draws 1kw at idle and turning on 2 hours before listening is not practicle for me. Thanks

I guess really im just looking for the sound characteristics as compared to each other and which one is going to give me a big rock concert soundstage, right now I'm leaning towards the fpb200 as i read that it has the fullest sound and shares some technologies of the other two amps, but thats based on what bits of information ive scrounged off the internet so I am open to some real world feedback