I have been using a RM Pro together with the RM Plugin app for more than a year, no issues as far as reliability is concerned.
The issue could be the limitations of the Broadlink skill which till today I am avoiding as it still looks like a work in progress (i.e. requires workarounds to get some types of devices to work).
Think of how you would change channels your cable box with your remote control, probably you need to press the numerical keys 3,0,1 or 7,1,1 in succession with some delay in between.
You need to map these actions into a macro so that you give 1 voice command to execute a series of IR blasts to your cable box. If the Broadlink skill doesn't support macros then you are out of luck. RM Plugin supports macros and you can set time interval delays between each action in the macro. It's similar to Alexa Routines but that doesn't have support for time interval delays at this moment.