Suitcase is a lot better than this, because Bottle of Airag and Salt Steppe Atlas can be sold in the Khanate to buy 1.92 more Crackling Devices. You can sell those to the Rat Market. It's a little worse than the Silks if you value your actions, but not by much.

Speaking of, you should include the action cost of selling to the Rats -- if you value your action at 6 Echoes, then Silks are 25.1 Echoes-per-Deed and Suitcase is 24.4 EpD.