STC is solid and people seem to like their videos a lot. With that said, they have two issues: they just do not have that many questions compared to other prep providers. Also, from my perspective their technology needs work. This is subjective and not an exact science. STC has been in business for a long time and has its roots on the institutional side of this business. Although, I think they have tried to be more appealing to the average retail client more recently. In addition to STC being around for a long term, their content very reliable.