Well rescan is not really a concern here, since we are talking about bitcoind node that's up 24/7 on a dedicated server.
I'm more concerned if it would make using the wallet slower for the front end app or cause other problems.
That doesn't matter because Armory takes the blockchain data and reprocesses it into the Armory database and that is what takes long. Rescan means Armory is scanning that data for transactions associated with the addresses in the wallet.
Check OP twice, please.