is it the same filter?
No. It's not the same filter.
which is better?
The filtering features on both are pretty much the same.
Price is by now also the same on both (besides for 'custom filtering', which is $30 by Meshimer and $35 by KosherLGClassic).
Pros of KosherLGClassic: Can be installed remotely; no need to go down to a filtering location.
Pros of Meshimer: Once filtered it is not connected to their cloud website (I'm not comfortable not knowing what information about my device continuously gets uploaded to somewhere..).