Well, no the Harmony isn't the only option.  JP1 remotes. like the RCA RCRP05B ($20) will do this job well.  So will the Comcast remote. although it would benefit from having one more device button.  The Samsung, LG, and Onkyo all have a full set of discrete IR commands, so a "help button" isn't necessary.  (It is also possible to setup some Harmonys so that they use discretes also.)  

The RCRP05B is highly reliable, and you can expect the batteries to last for at least a year.  Using the RMIR software, the remote can be used to power on and set the various inputs by pressing the TV, DVD, or Audio buttons. 

You will need to buy (or assemble) a JP1 flash cable ($20-$30).  The benefit is high relieability, long battery life, and  the system is cheap.