Payment channels alone are only a good solution if you consider it acceptable to establish a payment channel with everyone you want to pay. So, in other words, it only makes sense for recurring payments to the same merchant, and you pay the blockchain fee once for each merchant you want to pay. Consequently, if you only pay once you pay the same fee as an on-chain transaction, and if you pay 1000 times you pay, in average, 1000th the blockchain fee per payment.

+1, I have another project on payment channels, coming soon