I have the smaller version of the harmony and its bollox tbh.Very slow.
I used a dreambox profile off of their software and then had to add certain button myself by programming them directly off the remote.
You wont find a profile that will work 100%,you can use one as a base but you will still have to manually program some of the buttons off your original remote.
I dont think there is anything you can do about the delay,it seems to happen on everything I operate with it.You have to remember its like a mini computer so they have to process the information more than a standard remote so it takes longer.