Personally, I'm really hesitant to sign Freddy to a bigger contract than he currently has that runs into his late 30's. We don't have the cap space to give him a significant raise and while goalies are unpredictable in general, at 30, he's at the back-end of his prime.
Murray's 26. His next contract will take him through his prime. He's also coming off a really bad year, so there's an element of risk but if you believe in him as a goalie, there's also an opportunity to get him at a below market rate going forward (which, again, given our cap situation, is needed).
In short, whether Murray is an upgrade on Andersen now might not matter if he's close to as good, maybe a little cheaper, and because he's younger. Just IMHO.