I have never run my SA 250 bridged in mono,nor have I had the opportunity to hear them as such, so I can't be of much help. However, the second part of your question can best be answered by shooting an email over to Peter Thomson at Plinius NZ. I have asked Peter lots of questions regarding my amp and he never fails to answer and provide great and friendly info. He really knows his stuff. You can email him at: peter.t@froggy.com.au
Good luck with your quest...Regards-Ken
Good luck with your quest...Regards-Ken