Electronic payments are generally processed faster than a paper check. But really, it's just a personal preference choice.
You can enter your direct debit info in TurboTax, or pay directly on the IRS website. See below.
https://ttlc.intuit.com/questions/2579955-can-i-use-direct-debit-to-pay-the-irs-even-though-i-m-not-...