I have a TSR theory:
As we know the 9500's can miss quick trigger pulls because of a less than .5 second initial delay (doesint miss I/O). Now this TSR feature can be added to the X50's and has the ability to be turned on/off (adding subtracting a delay that wasn’t there).
The TSR feature is included with the ix and may have always been but wasn’t advertised.
I’m thinking the TSR feature is what was causing the quick trigger delay and now its being made a switchable feature to allow for quick trigger alerts.
Sounds possible to me but only Escort could answer that (or maybe not). So time will tell when that feature is tested on the ix's.