I've owned my hop rocket for about a year and never used it. Primarily because I didn't want to deal with scaling my recipe to account for the loss. Anyway, I brewed a Black Brett IPA on Saturday and decided it was time to use it.
It will likely be the last time also for one reason: endless amounts of hop material in my plate chiller. Other than that it worked as advertised. I'll probably sell it. I don't think it will work as a Randalizer either - I imaging keg quick disconnects would be constantly plugged.
So if you plan to use one, use an immersion chiller, or plan on LOTS of back flushing. And yes, I used whole hops.