We have 4 servers just doing IVR processing over 1.5 Million calls per month with extensive customizations including mainframe screen-scraping and Oracle database logging. We haven’t used Speech recognition yet, but I know that it works well with Nuance. Once we migrate our systems to ver 2.2, we will be implementing speech recognition through our IVR’s.
We briefly looked at Telephony@Work and seem to remember that it also uses the Nuace Processing engine.
Hope this info is helpful.
Can you please let me know what you find in your evaluations and which product you select.