Used both. TurboTax is a bit more user-friendly IMO but H&R Block tends to be cheaper for similar features. Accuracy wise both are solid if your return is straightforward. But if u r self-employed or have investments, H&R Block tends to push u toward a human tax pro sooner.
I used H&R Block online this year after years of using TurboTax. It was basically the same flow but $40 cheaper when all was said and done. Honestly if your taxes are simple both are fine.