You already have a Canonet? To me, the Konica S2 is just like the QL17 on steroids: bigger. However, I won't say better (I'm tempted) because of the size, precisely.
The good thing about the Konica is that it has a couple more shutterspeeds (slower) than the Canonet. I believe it shoots 1 full second and then 1/2, whereas the Canonet starts at 1/4.
I had a good Konica S2, but almost never used it, so I sold it. I don't regret it, though, but must tell you that the VF has nothing to envy from Leica.
Regarding the battery... I wouldn't worry about it. The meter will work fine with it!