For example for a 1 MB block, does the extra Tx index database take up another 100 kB on average?
And a follow-up: once my node has completed -reindex after setting txindex=1 can I COPY the blockchain AND the TX index database together to other nodes? I know the blockchain can be copied but I'm not sure if the new node needs to reindex the blockchain itself or if the index database copies over as well.