I hope Iris lives on in some form or another. It’s my go-to sampler. I’ve looked at a few of the more powerful sampling systems (Falcon, Kontakt, etc.) but for the amount of sampling I do, which is to say about one in 10 songs uses a non-drum sample, I don’t want to learn a really deep sampler.
I have some of the Exponential audio stuff I either got for free or super cheap after the acquisition of Exponential by Izotope, and it’s OK. Other than Excalibur, I don’t think any of it has made a mix because there was an issue for a while where those plugins would output mono only in FL studio. I just quit using them and I have Eventide/Valhalla stuff now.
Excalibur actually is a pretty cool idea, kind of like the modern equivalent of the early delay line effect boxes that you could set up to do chorus, delay, reverb, etc by directly controlling the delay taps. But also with modern CPU power so it can be very clean, you can add distortion, etc. I’ve never programmed anything, but there are a ton of presets that do what they say they will, and they’re super tweakable.