You can actually purchase the protection plan from turbotax which has your return reviewed by a professional and offers a guarantee just like using a CPA. I think the cost varies on the size of your return and what type you are filing but it is available.

I have used it for several years now and it's a great tool when you use what they have to offer. Of course it comes with a price and you have to pay for the features you use, however a good CPA will cost you much more.

This year I will be using a CPA due to owning my own business and the fact my return has gotten more complicated, however, I still think turbotax is a good product.