I have used H&R Block's tax software for several years. It has proven to be totally accurate in alll my submissions. No problems with submissions to IRS and State.
Pros: Easy to prepare, Maximizes refund, Easy to import documents, Fast
The software entered a large part of my RMD in the wrong line, so It looks like I didn't withdraw enough. Now the IRS tells me I need to submit a written and mailed 1040X to correct the clerical error. I did everything correctly and still the data was entered in the wrong place. PS: there is no way to do the 1040X in the program because the form does not have a way to do that except for Part III explanation. And also the program will not allow me to amend the State IT201X because it is locked to the erroneous !040SR and 1040X.