Originally Posted by Sammy2
If an RF remote is used in both locations using the RF to IR repeater, yes it will cause problems.
Unless there's a way to pair the remote to the RF to IR repeater, that would be true. I'm not familiar enough with the Harmony line to know if they pair them or not - if not, that would be a pretty major oversight as it could cause lots of issues for neighbors in apartment buildings if more than one is using a Harmony with RF.
If the IR repeater is not used in one of the locations, you might as well go with an IR remote in that location. The IR signal will not get through the wall to the other room so IMHO it is less likely to cause the problems with which the OP is concerned.
He said that there isn't a wall separating the 2 areas:
Our Echo is in a loft above the same room with the HTPC, no walls etc.
So stray IR commands could definitely cause issues for him depending on how the equipment is situated in the 2 areas.