Sounds like the SX50 is just not working out for you, which is probably very frustrating if you did not have all the problems mentioned when using the SX40. I would have traded for the MFT system you spoke of in another post, with a ten day trial period to make sure each party would be happy with the deal.
Only problem with the above scenario is if supezooms are in your blood. If thats the case, you'll not be happy till you get another superzoom.
I went through 3 or 4 purchases before finding one I liked. Good luck on your quest