If it's new code, I certainly agree, go with what's current and flexible. On the other hand, if the OP's (TheEnigma's) statement

I've got it working, using MD5

means that it's working in production, and switching would mean changeover, debugging and testing, then you have to weigh that cost against the risk of continuing with MD5, which apears minimal if, as the OP says, there are no secrets and no money involved.