I didn't see much change in CPU usage, with the exception of one program, which jumped from ~70% usage to ~82%. It's the 5F6A Bassguy patch, with one extra IR loaded - the 6" room sound one. Removing one of the two original IRs drops usage down to ~77% or so. Weird.
I was talking about using the new truncating feature for the IR's in the Cab block...by going down to 512 on a couple of my IR's in a 3 IR mix I was able to free up space for one more Plex delay block.