I want to agree with this, but... Siegfried and Roy have been gone for a long time. The tigers have been perpetually less featured each year. The Poker room was reduced and then closed. The volcano was tired. I've had some great room views of it, and after the first "eruption" or two, I found I kind of couldn't care anymore. The buffet closed with no plans to ever reopen.
The rooms are nice, and I suspect they will remain nice under Hard Rock management.
The only question becomes "what will the chips look like"? Only then will I miss the Mirage. Everything else Mirage-worthy was already faded or