I have a little more complicated tax returns due to me working in 3-4 states per year. I tried filing my own taxes for 2011 via H&R Blocks online service and ended up having to pay quite a bit in additional taxes. Duane re-filed my 2011 tax returns and prepared my 2012 tax returns and found a lot of refunds that the online services did not calculate.
In addition to the additional refunds Duane was also less expensive than the online services even with the free federal filing as they typically charge $40 per state that you file with. Some states don't accept electronic submissions so you're paying for a service that you still have to print and send in your own taxes.
Plus Duane's a really nice guy so you've got that going for you, which is nice.